diff --git a/2024-2025 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred)/F. Fix Flooded Floor.cpp b/2024-2025 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred)/F. Fix Flooded Floor.cpp
new file mode 100644
index 0000000..423a241
--- /dev/null
+++ b/2024-2025 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred)/F. Fix Flooded Floor.cpp	
@@ -0,0 +1,167 @@
+/* Problem URL: https://codeforces.com/problemset/problem/2052/F */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    array<string, 2> a;
+    cin >> a[0] >> a[1];
+
+    vvi memo(n, vi(4, -1));
+
+    function<int(int, int)> dp = [&](int i, int mask) -> int {
+        if (i >= n) {
+            return mask == 0;
+        }
+
+        int &ans = memo[i][mask];
+        if (ans != -1) {
+            return ans;
+        }
+
+        ans = 0;
+
+        int bit1 = mask & 1;
+        int bit2 = (mask >> 1) & 1;
+
+        if ((bit1 && a[0][i] == '#') || (bit2 && a[1][i] == '#')) {
+            return 0;
+        }
+
+        if (mask == 0 && a[0][i] == '.' && a[1][i] == '.') {
+            ans = dp(i + 1, 0) + dp(i + 1, 3);
+            rmin(ans, 2);
+        } else {
+            int now = 0;
+            if (!bit1 && a[0][i] == '.') {
+                now |= 1;
+            }
+
+            if (!bit2 && a[1][i] == '.') {
+                now |= 2;
+            }
+
+            ans += dp(i + 1, now);
+            rmin(ans, 2);
+        }
+
+        return ans;
+    };
+
+    int ans = dp(0, 0);
+
+    if (ans == 0) {
+        cout << "None\n";
+        return;
+    }
+
+    if (ans == 1) {
+        cout << "Unique\n";
+        return;
+    }
+
+    if (ans == 2) {
+        cout << "Multiple\n";
+    }
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!)/D. Ones and Twos.cpp b/CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!)/D. Ones and Twos.cpp
new file mode 100644
index 0000000..3519ed1
--- /dev/null
+++ b/CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!)/D. Ones and Twos.cpp	
@@ -0,0 +1,221 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1896/D */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, q;
+    cin >> n >> q;
+
+    vi a(n);
+    cin >> a;
+
+    while (__builtin_popcount(n) != 1) {
+        n++;
+        a.push_back(0);
+    }
+
+    set<int> ones;
+    rep(i, n) {
+        if (a[i] == 1) {
+            ones.insert(i);
+        }
+    }
+
+    vi seg(n << 1);
+
+    nrep(i, n, n << 1) {
+        seg[i] = a[i - n];
+    }
+
+    for (int i = n - 1; i > 0; i--) {
+        seg[i] = seg[i * 2] + seg[i * 2 + 1];
+    }
+
+    auto update = [&](int i, int v) {
+        i += n;
+        seg[i] = v;
+        for (i >>= 1; i > 0; i >>= 1) {
+            seg[i] = seg[i * 2] + seg[i * 2 + 1];
+        }
+    };
+
+    function<int(int, int, int, int, int)> query = [&](int i, int l, int r, int tl, int tr) {
+        if (l > tr || r < tl) {
+            return 0;
+        }
+
+        if (l >= tl && r <= tr) {
+            return seg[i];
+        }
+
+        int mid = (l + r) >> 1;
+
+        return query(i * 2, l, mid, tl, tr) + query(i * 2 + 1, mid + 1, r, tl, tr);
+    };
+
+    int l1 = -1;
+    int r1 = -1;
+
+    if (!ones.empty()) {
+        l1 = *ones.begin();
+        r1 = *prev(ones.end());
+    }
+
+    while (q--) {
+        int op;
+        cin >> op;
+
+        if (op == 2) {
+            int i, v;
+            cin >> i >> v;
+            i--;
+
+            if (a[i] == 1) {
+                ones.erase(i);
+            }
+
+            a[i] = v;
+            update(i, v);
+
+            if (v == 1) {
+                ones.insert(i);
+            }
+
+            if (!ones.empty()) {
+                l1 = *ones.begin();
+                r1 = *prev(ones.end());
+            } else {
+                l1 = -1;
+                r1 = -1;
+            }
+
+            continue;
+        }
+
+        int s;
+        cin >> s;
+
+        if (s & 1) {
+            if (l1 == -1) {
+                cout << "NO\n";
+                continue;
+            }
+
+            if (ones.size() & 1) {
+                cout << (query(1, 0, n - 1, 0, n - 1) >= s ? "YES\n" : "NO\n");
+                continue;
+            }
+
+            int ans = max(query(1, 0, n - 1, 0, r1 - 1), query(1, 0, n - 1, l1 + 1, n - 1));
+            cout << (ans >= s ? "YES\n" : "NO\n");
+            continue;
+        }
+
+        if (ones.size() & 1) {
+            int ans = max(query(1, 0, n - 1, 0, r1 - 1), query(1, 0, n - 1, l1 + 1, n - 1));
+            cout << (ans >= s ? "YES\n" : "NO\n");
+            continue;
+        }
+
+        cout << (query(1, 0, n - 1, 0, n - 1) >= s ? "YES\n" : "NO\n");
+    }
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 1012 (Div. 1)/A. Simple Permutation.cpp b/Codeforces Round 1012 (Div. 1)/A. Simple Permutation.cpp
new file mode 100644
index 0000000..ceeb2ab
--- /dev/null
+++ b/Codeforces Round 1012 (Div. 1)/A. Simple Permutation.cpp	
@@ -0,0 +1,162 @@
+/* Problem URL: https://codeforces.com/problemset/problem/2089/A */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+const int MAXN = 2e5 + 1;
+bool prime[MAXN];
+
+void pre()
+{
+    fill(prime, prime + MAXN, true);
+    prime[1] = false;
+    prime[0] = false;
+    nrep(i, 2, MAXN) {
+        if (!prime[i]) {
+            continue;
+        }
+
+        for (int j = i << 1; j < MAXN; j += i) {
+            prime[j] = false;
+        }
+    }
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    // int n = 7;
+    // int cur = 3;
+    // nrep(i, 3, n + 1) {
+    //     cur += i;
+    //     cout << (cur + i - 1) / i << '\n';
+    // }
+
+    int l = n / 3;
+
+    int choice = l;
+    while (!prime[choice]) {
+        choice++;
+    }
+
+    int rm = 0;
+    int now = 1;
+    vi ans(n);
+
+    set<int> act;
+    rep(i, n) {
+        act.insert(i + 1);
+    }
+
+    rep(i, l) {
+        ans[i] = choice + rm * now;
+        act.erase(ans[i]);
+
+        if (now == 1) {
+            now = -1;
+            rm++;
+        } else {
+            now = 1;
+        }
+    }
+
+    nrep(i, l, n) {
+        ans[i] = *act.begin();
+        act.erase(act.begin());
+    }
+
+    cout << ans;
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 1029 (Div. 3)/G. Omg Graph.cpp b/Codeforces Round 1029 (Div. 3)/G. Omg Graph.cpp
new file mode 100644
index 0000000..e71310e
--- /dev/null
+++ b/Codeforces Round 1029 (Div. 3)/G. Omg Graph.cpp	
@@ -0,0 +1,175 @@
+/* Problem URL: https://codeforces.com/problemset/problem/2117/G */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, m;
+    cin >> n >> m;
+
+    V<tuple<ll, int, int>> edges(m);
+    for (auto &[c, u, v] : edges) {
+        cin >> u >> v >> c;
+        u--, v--;
+    }
+
+    sortv(edges);
+
+    vi dsu(n);
+    rep(i, n) {
+        dsu[i] = i;
+    }
+
+    function<int(int)> find_p = [&](int i) {
+        if (dsu[i] == i) {
+            return i;
+        }
+        return dsu[i] = find_p(dsu[i]);
+    };
+
+    auto join = [&](int a, int b) {
+        a = find_p(a);
+        b = find_p(b);
+        dsu[b] = a;
+        return a != b;
+    };
+
+    V<V<pair<int, ll>>> graph(n);
+
+    for (auto [c, u, v] : edges) {
+        if (join(u, v)) {
+            graph[u].emplace_back(v, c);
+            graph[v].emplace_back(u, c);
+        }
+    }
+
+    V<pair<ll, ll>> every;
+    every.reserve(n);
+    ll mians = OO;
+    ll maans = 0;
+
+    function<void(int, int, ll, ll)> dfs = [&](int i, int p, ll mi, ll ma) {
+        if (i == n - 1) {
+            mians = mi;
+            maans = ma;
+        }
+
+        every.emplace_back(mi, ma);
+
+        for (auto [j, c] : graph[i]) {
+            if (j == p) {
+                continue;
+            }
+
+            dfs(j, i, min(mi, c), max(ma, c));
+        }
+    };
+
+    dfs(0, 0, OO, 0);
+    
+    ll ans = OO;
+
+    for (auto [mi, ma] : every) {
+        rmin(ans, min(mians, mi) + max(maans, ma));
+    }
+
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 1048 (Div. 1)/C1. Maple and Tree Beauty (Easy Version).cpp b/Codeforces Round 1048 (Div. 1)/C1. Maple and Tree Beauty (Easy Version).cpp
new file mode 100644
index 0000000..9abf96d
--- /dev/null
+++ b/Codeforces Round 1048 (Div. 1)/C1. Maple and Tree Beauty (Easy Version).cpp	
@@ -0,0 +1,148 @@
+/* Problem URL: https://codeforces.com/problemset/problem/2138/C1 */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, k;
+    cin >> n >> k;
+
+    vi depth(n);
+    vi sums(n);
+    V<bool> leaf(n, true);
+
+    sums[0] = 1;
+
+    nrep(i, 1, n) {
+        int a;
+        cin >> a;
+        a--;
+
+        depth[i] = depth[a] + 1;
+        sums[depth[i]]++;
+        leaf[a] = false;
+    }
+
+    int maxdepth = oo;
+    rep(i, n) {
+        if (leaf[i]) {
+            rmin(maxdepth, depth[i]);
+        }
+    }
+
+    vi dp(n + 1);
+    dp[0] = 1;
+
+    rep(i, maxdepth) {
+        for (int j = n; j >= sums[i]; j--) {
+            dp[j] |= dp[j - sums[i]];
+        }
+    }
+
+    rep(i, n + 1) {
+        if (dp[i] && i <= k && n - i <= n - k) {
+            cout << maxdepth + 1 << '\n';
+            return;
+        }
+    }
+
+    cout << maxdepth << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 1060 (Div. 2)/A. Notelock.cpp b/Codeforces Round 1060 (Div. 2)/A. Notelock.cpp
new file mode 100644
index 0000000..4041387
--- /dev/null
+++ b/Codeforces Round 1060 (Div. 2)/A. Notelock.cpp	
@@ -0,0 +1,114 @@
+/* Problem URL: https://codeforces.com/contest/2154/problem/A */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    int t;
+    cin >> t;
+    while (t--) {
+        int n, k;
+        cin >> n >> k;
+        string s;
+        cin >> s;
+
+        V<bool> fds(n);
+
+        int ans = 0;
+
+        rep(i, n) {
+            if (s[i] != '1') {
+                continue;
+            }
+
+            bool valid = true;
+
+            for (int j = i - 1; j >= 0 && i - j + 1 <= k; j--) {
+                if (s[j] == '1') {
+                    valid = false;
+                    break;
+                }
+            }
+
+            ans += valid;
+        }
+
+        cout << ans << '\n';
+    }
+}
diff --git a/Codeforces Round 1060 (Div. 2)/B. Make it Zigzag.cpp b/Codeforces Round 1060 (Div. 2)/B. Make it Zigzag.cpp
new file mode 100644
index 0000000..7b6cc71
--- /dev/null
+++ b/Codeforces Round 1060 (Div. 2)/B. Make it Zigzag.cpp	
@@ -0,0 +1,117 @@
+/* Problem URL: https://codeforces.com/contest/2154/problem/B */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    int t;
+    cin >> t;
+    while (t--) {
+        int n;
+        cin >> n;
+        vl a(n);
+        cin >> a;
+
+        ll maximal = 0;
+        rep(i, n) {
+            rmax(maximal, a[i]);
+
+            if (i & 1) {
+                a[i] = maximal;
+            }
+        }
+
+        int ans = 0;
+
+        for (int i = 1; i < n; i += 2) {
+            if (a[i] <= a[i - 1]) {
+                int diff = a[i - 1] - a[i] + 1;
+                ans += diff;
+            }
+
+            if (i < n - 1 && a[i] <= a[i + 1]) {
+                int diff = a[i + 1] - a[i] + 1;
+                ans += diff;
+                a[i + 1] -= diff;
+            }
+        }
+
+        cout << ans << '\n';
+    }
+}
diff --git a/Codeforces Round 1060 (Div. 2)/C1. No Cost Too Great (Easy Version).cpp b/Codeforces Round 1060 (Div. 2)/C1. No Cost Too Great (Easy Version).cpp
new file mode 100644
index 0000000..165243b
--- /dev/null
+++ b/Codeforces Round 1060 (Div. 2)/C1. No Cost Too Great (Easy Version).cpp	
@@ -0,0 +1,168 @@
+/* Problem URL: https://codeforces.com/contest/2154/problem/C1 */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+int divs[(int)2e5 + 2];
+
+void pre()
+{
+    fill(divs, divs + (int)2e5 + 2, 1);
+
+    nrep(i, 2, 2e5 + 2) {
+        if (divs[i] != 1) {
+            continue;
+        }
+
+        for (int j = i; j <= (ll)2e5 + 1; j += i) {
+            divs[j] = i;
+        }
+    }
+}
+
+void solve()
+{
+        int n;
+        cin >> n;
+
+        vi a(n);
+        vi b(n);
+        cin >> a >> b;
+
+        set<int> primes;
+
+        auto getprimes = [&](int now) {
+            while (divs[now] != 1) {
+                if (primes.count(divs[now])) {
+                    return true;
+                }
+                primes.insert(divs[now]);
+                int prev = divs[now];
+                while (divs[now] == prev) {
+                    now /= divs[now];
+                }
+            }
+
+            return false;
+        };
+
+        auto checkprimes = [&](int now) {
+            while (divs[now] != 1) {
+                if (primes.count(divs[now])) {
+                    return true;
+                }
+
+                int prev = divs[now];
+                while (divs[now] == prev) {
+                    now /= divs[now];
+                }
+            }
+
+            return false;
+        };
+
+        rep(i, n) {
+            if (getprimes(a[i])) {
+                cout << "0\n";
+                return;
+            }
+        }
+
+        int ans = 2;
+
+        rep(i, n) {
+            if (checkprimes(a[i] + 1)) {
+                rmin(ans, 1);
+                break;
+            }
+        }
+
+        cout << ans << '\n';
+
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t = 1;
+    cin >> t;
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 1060 (Div. 2)/C2. No Cost Too Great (Hard Version).cpp b/Codeforces Round 1060 (Div. 2)/C2. No Cost Too Great (Hard Version).cpp
new file mode 100644
index 0000000..c62444c
--- /dev/null
+++ b/Codeforces Round 1060 (Div. 2)/C2. No Cost Too Great (Hard Version).cpp	
@@ -0,0 +1,193 @@
+/* Problem URL: https://codeforces.com/contest/2154/problem/C2 */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+const int maxn = 2e5 + 2;
+int divs[maxn];
+
+void pre()
+{
+    fill(divs, divs + maxn, 1);
+
+    nrep(i, 2, maxn) {
+        if (divs[i] != 1) {
+            continue;
+        }
+
+        for (int j = i; j < maxn; j += i) {
+            divs[j] = i;
+        }
+    }
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    V<pair<ll, int>> a(n);
+
+    repv(i, a) {
+        cin >> i.second;
+    }
+
+    repv(i, a) {
+        cin >> i.first;
+    }
+
+    set<int> primes;
+
+    auto getprimes = [&](int now) {
+        while (divs[now] != 1) {
+            if (primes.count(divs[now])) {
+                return true;
+            }
+            primes.insert(divs[now]);
+            int prev = divs[now];
+            while (divs[now] == prev) {
+                now /= divs[now];
+            }
+        }
+
+        return false;
+    };
+
+    auto findprimes = [&](int now) {
+        while (divs[now] != 1) {
+            if (primes.count(divs[now])) {
+                return true;
+            }
+            int prev = divs[now];
+            while (divs[now] == prev) {
+                now /= divs[now];
+            }
+        }
+
+        return false;
+    };
+
+    rep(i, n) {
+        if (getprimes(a[i].second)) {
+            cout << "0\n";
+            return;
+        }
+    }
+
+    sortv(a);
+
+    ll ans = a[0].first + a[1].first;
+    rep(i, n) {
+        if (findprimes(a[i].second + 1)) {
+            rmin(ans, a[i].first);
+        }
+    }
+
+    if (primes.empty()) {
+        cout << ans << '\n';
+        return;
+    }
+
+
+    repv(i, primes) {
+        if (a[0].second % i == 0) {
+            continue;
+        }
+
+        rmin(ans, (i - a[0].second % i) * a[0].first);
+    }
+
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 1060 (Div. 2)/D. Catshock.cpp b/Codeforces Round 1060 (Div. 2)/D. Catshock.cpp
new file mode 100644
index 0000000..ccaabb8
--- /dev/null
+++ b/Codeforces Round 1060 (Div. 2)/D. Catshock.cpp	
@@ -0,0 +1,171 @@
+/* Problem URL: https://codeforces.com/contest/2154/problem/D */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    vvi graph(n);
+
+    rep(i, n - 1) {
+        int a, b;
+        cin >> a >> b;
+        a--, b--;
+
+        graph[a].push_back(b);
+        graph[b].push_back(a);
+    }
+
+    vi color(n);
+    vi dis(n);
+
+    function<void(int, int)> dfs = [&](int i, int p) {
+        repv(j, graph[i]) {
+            if (j == p) {
+                continue;
+            }
+
+            dis[j] = dis[i] + 1;
+            color[j] = color[i] ^ 1;
+            dfs(j, i);
+        }
+    };
+
+    dfs(n - 1, n - 1);
+
+    int now = color[0];
+    V<pair<int, int>> edges;
+
+    rep(i, n - 1) {
+        edges.emplace_back(dis[i], i);
+    }
+
+    sort(all(edges), greater<>());
+
+    V<pair<int, int>> ops;
+
+    rep(i, n - 1) {
+        int j = edges[i].second;
+
+        if (color[j] == now) {
+            ops.emplace_back(1, 0);
+            now ^= 1;
+        }
+
+        ops.emplace_back(2, j + 1);
+        ops.emplace_back(1, 0);
+        now ^= 1;
+    }
+
+    cout << ops.size() << '\n';
+    repv(i, ops) {
+        cout << i.first;
+
+        if (i.first == 2) {
+            cout << ' ' << i.second;
+        }
+        
+        cout << '\n';
+    }
+    cout << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 1061 (Div. 2)/A. Pizza Time.cpp b/Codeforces Round 1061 (Div. 2)/A. Pizza Time.cpp
new file mode 100644
index 0000000..74e1e06
--- /dev/null
+++ b/Codeforces Round 1061 (Div. 2)/A. Pizza Time.cpp	
@@ -0,0 +1,115 @@
+/* Problem URL: https://codeforces.com/contest/2156/problem/A */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    ll n;
+    cin >> n;
+
+    ll ans = 0;
+    while (n > 2) {
+        ans += n / 3;
+        n = n / 3 + n % 3;
+    }
+
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 1061 (Div. 2)/B. Strange Machine.cpp b/Codeforces Round 1061 (Div. 2)/B. Strange Machine.cpp
new file mode 100644
index 0000000..212f54d
--- /dev/null
+++ b/Codeforces Round 1061 (Div. 2)/B. Strange Machine.cpp	
@@ -0,0 +1,141 @@
+/* Problem URL: https://codeforces.com/contest/2156/problem/B */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, q;
+    cin >> n >> q;
+    string a;
+    cin >> a;
+
+    bool pos = true;
+    rep(i, n) {
+        if (a[i] == 'B') {
+            pos = false;
+            break;
+        }
+    }
+
+    while (q--) {
+        ll x;
+        cin >> x;
+
+        if (pos) {
+            cout << x << '\n';
+            continue;
+        }
+
+        int now = 0;
+        while (x > 0) {
+            if (a[now % n] == 'A') {
+                x--;
+                now++;
+                continue;
+            }
+
+            now++;
+            x /= 2;
+        }
+
+        cout << now << '\n';
+    }
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 1061 (Div. 2)/C. Maximum GCD on Whiteboard.cpp b/Codeforces Round 1061 (Div. 2)/C. Maximum GCD on Whiteboard.cpp
new file mode 100644
index 0000000..8b3b3de
--- /dev/null
+++ b/Codeforces Round 1061 (Div. 2)/C. Maximum GCD on Whiteboard.cpp	
@@ -0,0 +1,167 @@
+/* Problem URL: https://codeforces.com/contest/2156/problem/C */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+const int MAXN = 2e5 + 1;
+int lim[MAXN];
+
+void pre()
+{
+    nrep(i, 1, MAXN) {
+        int low = 1;
+        int high = i / 3;
+        int ans = 0;
+        while (low <= high) {
+            int mid = (low + high) >> 1;
+
+            int cur = i - mid * 2;
+            int dis = cur % mid;
+
+            if (cur - dis >= mid + dis) {
+                ans = mid;
+                low = mid + 1;
+                continue;
+            }
+
+            high = mid - 1;
+        }
+
+        lim[i] = ans;
+    }
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, k;
+    cin >> n >> k;
+
+    vi a(n);
+    cin >> a;
+
+    vi count(n + 1);
+    auto getdivs = [&](int now) {
+        for (int i = 1; i * i <= now; i++) {
+            if (now % i == 0) {
+                count[i]++;
+                if (i * i != now) {
+                    count[now / i]++;
+                }
+            }
+        }
+    };
+
+    vvi rem(n + 2);
+
+    rep(i, n) {
+        rem[lim[a[i]] + 1].push_back(a[i]);
+    }
+
+    int ans = 1;
+    int c = 0;
+
+    nrep(i, 1, n + 1) {
+        repv(j, rem[i]) {
+            getdivs(j);
+            c++;
+        }
+
+        int cur = c - count[i];
+        if (cur <= k) {
+            ans = i;
+        }
+    }
+
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 1061 (Div. 2)/D. Find the Last Number.cpp b/Codeforces Round 1061 (Div. 2)/D. Find the Last Number.cpp
new file mode 100644
index 0000000..0212b43
--- /dev/null
+++ b/Codeforces Round 1061 (Div. 2)/D. Find the Last Number.cpp	
@@ -0,0 +1,159 @@
+/* Problem URL: https://codeforces.com/contest/2156/problem/D */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    int log = 32 - __builtin_clz(n);
+
+    set<int> cur;
+    rep(i, n - 1) {
+        cur.insert(i + 1);
+    }
+
+    set<int> all;
+    rep(i, n) {
+        all.insert(i + 1);
+    }
+
+    rep(i, log) {
+        vi ans(cur.size());
+        array<int, 2> val = {};
+
+        auto it = cur.begin();
+        rep(j, ans.size()) {
+            cout << "? " << *it << ' ' << (1 << i) << endl;
+            cin >> ans[j];
+            val[ans[j]]++;
+            it++;
+        }
+
+        array<int, 2> act = {};
+        repv(j, all) {
+            act[((j >> i) & 1)]++;
+        }
+
+        int tmp = act[1] != val[1];
+
+        auto itr = all.begin();
+        while (itr != all.end()) {
+            if (((*itr >> i) & 1) != tmp) {
+                itr = all.erase(itr);
+           } else {
+                itr++;
+           }
+        }
+
+        it = cur.begin();
+        rep(i, ans.size()) {
+            if (ans[i] == tmp) {
+                it++;
+            } else {
+                it = cur.erase(it);
+            }
+        }
+    }
+
+    cout << "! " << *all.begin() << endl;
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 1062 (Div. 4)/D. Yet Another Array Problem.cpp b/Codeforces Round 1062 (Div. 4)/D. Yet Another Array Problem.cpp
new file mode 100644
index 0000000..f6f9ec1
--- /dev/null
+++ b/Codeforces Round 1062 (Div. 4)/D. Yet Another Array Problem.cpp	
@@ -0,0 +1,132 @@
+/* Problem URL: https://codeforces.com/contest/2167/problem/D */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+vi primes;
+
+void pre()
+{
+    V<bool> prime(2e5 + 1);
+
+    prime[1] = true;
+    nrep(i, 2, 200001) {
+        if (prime[i]) {
+            continue;
+        }
+
+        primes.push_back(i);
+
+        for (int j = i * 2; j <= 2e5; j += i) {
+            prime[j] = true;
+        }
+    }
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+    vl a(n);
+    cin >> a;
+
+    repv(i, primes) {
+        rep(j, n) {
+            if (a[j] % i != 0) {
+                cout << i << '\n';
+                return;
+            }
+        }
+    }
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 1062 (Div. 4)/E. khba Loves to Sleep!.cpp b/Codeforces Round 1062 (Div. 4)/E. khba Loves to Sleep!.cpp
new file mode 100644
index 0000000..70cf2e9
--- /dev/null
+++ b/Codeforces Round 1062 (Div. 4)/E. khba Loves to Sleep!.cpp	
@@ -0,0 +1,187 @@
+/* Problem URL: https://codeforces.com/contest/2167/problem/E */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, k;
+    ll x;
+    cin >> n >> k >> x;
+
+    vl a(n);
+    cin >> a;
+
+    sortv(a);
+    a.erase(unique(all(a)), a.end());
+
+    if (x - a.size() + 1 < k) {
+        rep(i, k) {
+            cout << i << ' ';
+        }
+        cout << '\n';
+        return;
+    }
+
+    priority_queue<tuple<ll, ll, ll, ll, ll, int>> pq;
+    if (a[0] != 0) {
+        pq.emplace(a[0], 0, 0, -1e9, a[0], -1);
+    }
+    if (a.back() != x) {
+        pq.emplace(x - a.back(), x, x, a.back(), 2e9, -2);
+    }
+
+    nrep(i, 1, a.size()) {
+        if (a[i] == a[i - 1] - 1) {
+            continue;
+        }
+
+        ll med = (a[i] + a[i - 1]) >> 1;
+        ll dis = min(a[i] - med, med - a[i - 1]);
+
+        pq.emplace(dis, med, med, a[i - 1], a[i], i);
+    }
+
+    set<tuple<int, ll, ll>> ranges;
+    while (k--) {
+        auto [d, l, r, lim1, lim2, id] = pq.top();
+        pq.pop();
+
+        if (l < 0 || l <= lim1 || r >= lim2 || r > x) {
+            k++;
+            continue;
+        }
+
+        auto itr = ranges.lower_bound({id, -1, -1});
+        if (itr != ranges.end() && get<0>(*itr) == id) {
+            ranges.erase(itr);
+        }
+
+        ranges.emplace(id, l, r);
+
+        ll l1 = l - 1;
+        ll r1 = r;
+        ll l2 = l;
+        ll r2 = r + 1;
+        ll dis1 = min(l1 - lim1, lim2 - r1);
+        ll dis2 = min(l2 - lim1, lim2 - r2);
+
+        if (l1 < max(0LL, lim1 + 1) || r1 > min(x, lim2 - 1)) {
+            dis1 = -1;
+        }
+        if (l2 < max(0LL, lim1 + 1) || r2 > min(x, lim2 - 1)) {
+            dis2 = -1;
+        }
+
+        if (dis1 >= dis2) {
+            pq.emplace(dis1, l1, r1, lim1, lim2, id);
+            continue;
+        }
+        pq.emplace(dis2, l2, r2, lim1, lim2, id);
+    }
+
+    repv(i, ranges) {
+        auto [id, lim1, lim2] = i;
+        nrep(j, lim1, lim2 + 1) {
+            cout << j << ' ';
+        }
+    }
+    cout << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 1062 (Div. 4)/F. Tree, TREE!!!.cpp b/Codeforces Round 1062 (Div. 4)/F. Tree, TREE!!!.cpp
new file mode 100644
index 0000000..9fc10f7
--- /dev/null
+++ b/Codeforces Round 1062 (Div. 4)/F. Tree, TREE!!!.cpp	
@@ -0,0 +1,167 @@
+/* Problem URL: https://codeforces.com/contest/2167/problem/F */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, k;
+    cin >> n >> k;
+
+    vvi graph(n);
+
+    rep(i, n - 1) {
+        int a, b;
+        cin >> a >> b;
+        a--, b--;
+
+        graph[a].push_back(b);
+        graph[b].push_back(a);
+    }
+
+    ll ans = n;
+
+    vl dp(n);
+
+    function<ll(int, int)> dfs = [&](int i, int p) {
+        dp[i] = 1;
+
+        repv(j, graph[i]) {
+            if (j == p) {
+                continue;
+            }
+
+            dp[i] += dfs(j, i);
+        }
+
+        return dp[i];
+    };
+
+    dfs(0, 0);
+
+    function<void(int, int)> reroot = [&](int i, int p) {
+        repv(j, graph[i]) {
+            ll now = n - dp[j];
+
+            if (now < k) {
+                continue;
+            }
+
+            ans += dp[j];
+        }
+
+        ll prev = dp[i];
+        repv(j, graph[i]) {
+            if (j == p) {
+                continue;
+            }
+            dp[i] = n - dp[j];
+            reroot(j, i);
+        }
+
+        dp[i] = prev;
+
+        return;
+    };
+
+    reroot(0, 0);
+
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 1062 (Div. 4)/G. Mukhammadali and the Smooth Array.cpp b/Codeforces Round 1062 (Div. 4)/G. Mukhammadali and the Smooth Array.cpp
new file mode 100644
index 0000000..17c977a
--- /dev/null
+++ b/Codeforces Round 1062 (Div. 4)/G. Mukhammadali and the Smooth Array.cpp	
@@ -0,0 +1,156 @@
+/* Problem URL: https://codeforces.com/contest/2167/problem/G */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        if (i.empty()) {
+            cout << '\n';
+            continue;
+        }
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    vl a(n);
+    vl c(n);
+    cin >> a >> c;
+
+    map<ll, int> var;
+    repv(i, a) {
+        var[i] = 0;
+    }
+
+    int v = 0;
+    repv(i, var) {
+        i.second = v;
+        v++;
+    }
+
+    repv(i, a) {
+        i = var[i];
+    }
+    var.clear();
+
+    vvl dp(2, vl(n));
+    int now = 0;
+
+    rep(i, n) {
+        int prev = now^1;
+
+        ll mi = OO;
+        rep(j, a[i]) {
+            rmin(mi, dp[prev][j]);
+            dp[now][j] = mi + c[i];
+        }
+
+        rmin(mi, dp[prev][a[i]]);
+        dp[now][a[i]] = mi;
+
+        nrep(j, a[i] + 1, n) {
+            rmin(mi, dp[prev][j]);
+            dp[now][j] = mi + c[i];
+        }
+
+        now ^= 1;
+    }
+
+    cout << *min_element(all(dp[now^1])) << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 832 (Div. 2)/D. Yet Another Problem.cpp b/Codeforces Round 832 (Div. 2)/D. Yet Another Problem.cpp
new file mode 100644
index 0000000..d9dc22c
--- /dev/null
+++ b/Codeforces Round 832 (Div. 2)/D. Yet Another Problem.cpp	
@@ -0,0 +1,190 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1747/D */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 0
+
+void solve()
+{
+    int n, q;
+    cin >> n >> q;
+
+    vi a(n);
+    cin >> a;
+
+    vi pref(n + 1);
+    vi zero(n + 1);
+    unordered_map<int, vi> var;
+    unordered_map<int, vi> odd;
+    unordered_map<int, vi> even;
+    rep(i, n) {
+        pref[i + 1] = pref[i] ^ a[i];
+        zero[i + 1] = zero[i] + (a[i] == 0);
+        var[pref[i + 1]].push_back(i);
+        if (i & 1) {
+            odd[pref[i + 1]].push_back(i);
+        } else {
+            even[pref[i + 1]].push_back(i);
+        }
+    }
+
+
+    while (q--) {
+        int l, r;
+        cin >> l >> r;
+        l--, r--;
+
+        if (zero[r + 1] - zero[l] == r - l + 1) {
+            cout << "0\n";
+            continue;
+        }
+
+        if (r - l <= 1) {
+            cout << "-1\n";
+            continue;
+        }
+
+        int xo = pref[r + 1] ^ pref[l];
+        if (xo != 0) {
+            cout << "-1\n";
+            continue;
+        }
+
+        if ((r - l + 1) & 1) {
+            cout << "1\n";
+            continue;
+        }
+
+        auto fds = var.find(pref[r + 1]);
+        if (fds == var.end()) {
+            cout << "-1\n";
+        }
+
+        vi &tmp = fds->second;
+        auto one = lower_bound(all(tmp), l);
+        auto two = lower_bound(all(tmp), r);
+
+        if (two != tmp.begin()) {
+            two--;
+        }
+
+        if ((one != tmp.end() && *one == l) || (two != tmp.end() && *two == r - 1)) {
+            cout << "1\n";
+            continue;
+        }
+
+        if (r & 1) {
+            vi &act = even[pref[r + 1]];
+            auto itr = lower_bound(all(act), l);
+            if (itr == act.end() || *itr > r) {
+                cout << "-1\n";
+                continue;
+            }
+        } else {
+            vi &act = odd[pref[r + 1]];
+            auto itr = lower_bound(all(act), l);
+            if (itr == act.end() || *itr > r) {
+                cout << "-1\n";
+                continue;
+            }
+        }
+
+        cout << "2\n";
+    }
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 839 (Div. 3)/D. Absolute Sorting.cpp b/Codeforces Round 839 (Div. 3)/D. Absolute Sorting.cpp
new file mode 100644
index 0000000..a31bfa2
--- /dev/null
+++ b/Codeforces Round 839 (Div. 3)/D. Absolute Sorting.cpp	
@@ -0,0 +1,130 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1772/D */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    vl a(n);
+    cin >> a;
+
+    ll l = 0;
+    ll r = 1e9;
+
+    nrep(i, 1, n) {
+        if (a[i] < a[i - 1]) {
+            rmax(l, (a[i] + a[i - 1] + 1) >> 1);
+        }
+
+        if (a[i] > a[i - 1]) {
+            rmin(r, (a[i] + a[i - 1]) >> 1);
+        }
+    }
+
+    if (l > r) {
+        cout << "-1\n";
+        return;
+    }
+
+    cout << l << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 843 (Div. 2)/C. Interesting Sequence.cpp b/Codeforces Round 843 (Div. 2)/C. Interesting Sequence.cpp
new file mode 100644
index 0000000..e246b7e
--- /dev/null
+++ b/Codeforces Round 843 (Div. 2)/C. Interesting Sequence.cpp	
@@ -0,0 +1,161 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1775/C */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    ll n, x;
+    cin >> n >> x;
+
+    auto get = [&](ll l, ll r) {
+        ll step = 1;
+        while (l != r) {
+            l >>= 1;
+            r >>= 1;
+            step <<= 1;
+        }
+
+        return step * l;
+    };
+
+    ll low = n;
+    ll high = 5e18;
+    ll ans = -1;
+    while (low <= high) {
+        ll mid = (high - low) / 2 + low;
+
+        ll tmp = get(n, mid);
+
+        auto test = [&]() {
+            rep(i, 63) {
+                ll bit1 = (tmp >> i) & 1;
+                ll bit2 = (x >> i) & 1;
+
+                if (!bit1 && bit2) {
+                    return 2;
+                }
+
+                if (bit1 && !bit2) {
+                    return 1;
+                }
+            }
+
+            return 0;
+        };
+
+        int g = test();
+
+        if (!g) {
+            ans = mid;
+            high = mid - 1;
+            continue;
+        }
+
+        if (g == 1) {
+            low = mid + 1;
+            continue;
+        }
+
+        high = mid - 1;
+    }
+
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 854 by cybercats (Div. 1 + Div. 2)/D1. Hot Start Up (easy version).cpp b/Codeforces Round 854 by cybercats (Div. 1 + Div. 2)/D1. Hot Start Up (easy version).cpp
new file mode 100644
index 0000000..7e3208e
--- /dev/null
+++ b/Codeforces Round 854 by cybercats (Div. 1 + Div. 2)/D1. Hot Start Up (easy version).cpp	
@@ -0,0 +1,155 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1799/D1 */
+
+#include <bits/stdc++.h>
+#include <algorithm>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, k;
+    cin >> n >> k;
+
+    vi a(n);
+    repv(i, a) {
+        cin >> i;
+        i--;
+    }
+
+    V<pair<ll, ll>> prog(k);
+    repv(j, prog) {
+        cin >> j.first;
+    }
+    repv(j, prog) {
+        cin >> j.second;
+    }
+
+    vi prev(n, -1);
+    vi pos(k, -1);
+
+    vl pref(n + 2);
+    pref[1] = prog[a[0]].first;
+    nrep(i, 1, n) {
+        pref[i + 1] = pref[i] + (a[i] == a[i - 1] ? prog[a[i]].second : prog[a[i]].first);
+    }
+    pref[n + 1] = pref[n];
+
+    vl dp(n + 1, 0);
+    dp[0] = prog[a[0]].first;
+
+    nrep(i, 1, n) {
+        prev[i] = pos[a[i]];
+        pos[a[i]] = i;
+
+        if (prev[i] == -1) {
+            dp[i] = dp[i - 1] + prog[a[i]].first;
+            continue;
+        }
+
+        if (prev[i] == i - 1) {
+            dp[i] = dp[i - 1] + prog[a[i]].second;
+        }
+
+        ll cur = dp[prev[i] + 1] + prog[a[i]].second + pref[i] - pref[prev[i] + 2];
+
+        dp[i] = min(dp[i - 1] + prog[a[i]].first, cur);
+    }
+
+    cout << dp[n - 1] << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 872 (Div. 1)/A. LuoTianyi and the Show.cpp b/Codeforces Round 872 (Div. 1)/A. LuoTianyi and the Show.cpp
new file mode 100644
index 0000000..eefb21a
--- /dev/null
+++ b/Codeforces Round 872 (Div. 1)/A. LuoTianyi and the Show.cpp	
@@ -0,0 +1,149 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1824/A */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, m;
+    cin >> n >> m;
+
+    vi a(n);
+    cin >> a;
+
+    vi pref(m + 2);
+    vi empty(m + 1);
+
+    int right = 0;
+    int left = 0;
+
+    repv(i, a) {
+        if (i == -1) {
+            left++;
+            continue;
+        }
+
+        if (i == -2) {
+            right++;
+            continue;
+        }
+
+        pref[i] = 1;
+    }
+
+    rep(i, m + 1) {
+        pref[i + 1] += pref[i];
+    }
+
+    int ans = min(max(pref.back() + right, pref.back() + left), m);
+
+    nrep(i, 1, m + 1) {
+        if (pref[i] == pref[i - 1]) {
+            continue;
+        }
+
+        int guys1 = pref.back() - pref[i];
+        int guys2 = pref[i - 1];
+
+        rmax(ans, min(pref.back() - guys1 - guys2 + min(guys1 + right, m - i) + min(guys2 + left, i - 1), m));
+    }
+    
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 891 (Div. 3)/D. Strong Vertices.cpp b/Codeforces Round 891 (Div. 3)/D. Strong Vertices.cpp
new file mode 100644
index 0000000..26bf640
--- /dev/null
+++ b/Codeforces Round 891 (Div. 3)/D. Strong Vertices.cpp	
@@ -0,0 +1,132 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1857/D */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    vl a(n);
+    cin >> a;
+
+    ll maximal = -1e12;
+
+    repv(i, a) {
+        ll now;
+        cin >> now;
+        i -= now;
+        rmax(maximal, i);
+    }
+
+    set<int> ans;
+    rep(i, n) {
+        if (a[i] == maximal) {
+            ans.insert(i + 1);
+        }
+    }
+
+    cout << ans.size() << '\n';
+    repv(i, ans) {
+        cout << i << ' ';
+    }
+    cout << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 896 (Div. 1)/B1. Candy Party (Easy Version).cpp b/Codeforces Round 896 (Div. 1)/B1. Candy Party (Easy Version).cpp
new file mode 100644
index 0000000..6590f79
--- /dev/null
+++ b/Codeforces Round 896 (Div. 1)/B1. Candy Party (Easy Version).cpp	
@@ -0,0 +1,181 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1868/B1 */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    vi a(n);
+    ll total = 0;
+    repv(i, a) {
+        cin >> i;
+        total += i;
+    }
+
+    if (total % n) {
+        cout << "No\n";
+        return;
+    }
+
+    total /= n;
+
+    vi rem(32);
+    vi add(32);
+    int wild = 0;
+
+    rep(i, n) {
+        if (a[i] == total) {
+            wild++;
+            continue;
+        }
+
+        int x2 = 0;
+        int y2 = -1;
+        rep(j, 32) {
+            ll now = 1LL << x2;
+
+            if (total - a[i] + now <= 0) {
+                x2++;
+                continue;
+            }
+
+            if (__builtin_popcountll(total - a[i] + now) == 1) {
+                y2 = 63 - __builtin_clzll(total - a[i] + now);
+                break;
+            }
+
+            x2++;
+        }
+
+        if (y2 == -1) {
+            cout << "No\n";
+            return;
+        }
+
+        int re = rem[y2];
+        int ad = add[x2];
+
+        if (re) {
+            rem[y2]--;
+        } else {
+            add[y2]++;
+        }
+
+        if (ad) {
+            add[x2]--;
+        } else {
+            rem[x2]++;
+        }
+    }
+
+    rep(i, 32) {
+        if (rem[i] != add[i] || rem[i] > wild) {
+            cout << "No\n";
+            return;
+        }
+
+        wild -= rem[i];
+    }
+
+    cout << "Yes\n";
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 898 (Div. 4)/H. Mad City.cpp b/Codeforces Round 898 (Div. 4)/H. Mad City.cpp
new file mode 100644
index 0000000..68f1708
--- /dev/null
+++ b/Codeforces Round 898 (Div. 4)/H. Mad City.cpp	
@@ -0,0 +1,221 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1873/H */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, a, b;
+    cin >> n >> a >> b;
+    a--, b--;
+
+    vi dsu(n);
+    rep(i, n) {
+        dsu[i] = i;
+    }
+
+    function<int(int)> find_p = [&](int i) {
+        if (dsu[i] == i) {
+            return dsu[i];
+        }
+        return dsu[i] = find_p(dsu[i]);
+    };
+
+    auto join = [&](int a, int b) {
+        a = find_p(a);
+        b = find_p(b);
+        dsu[b] = a;
+        return a == b;
+    };
+
+    vi loop;
+    pair<int, int> edge;
+
+    vvi graph(n);
+    rep(i, n) {
+        int u, v;
+        cin >> u >> v;
+        u--, v--;
+
+        if (!join(u, v)) {
+            graph[u].push_back(v);
+            graph[v].push_back(u);
+            continue;
+        }
+
+        edge = {u, v};
+    }
+
+    vi depth(n, -1);
+    vi parent(n);
+
+    function<void(int, int)> dfs = [&](int i, int p) {
+        depth[i] = depth[p] + 1;
+        parent[i] = p;
+
+        repv(j, graph[i]) {
+            if (j == p) {
+                continue;
+            }
+
+            dfs(j, i);
+        }
+    };
+
+    dfs(0, 0);
+
+    int u = edge.first;
+    int v = edge.second;
+
+    if (depth[u] > depth[v]) {
+        swap(u, v);
+    }
+
+    int diff = depth[v] - depth[u];
+    while (diff--) {
+        loop.push_back(v);
+        v = parent[v];
+    }
+
+    while (u != v) {
+        loop.push_back(u);
+        loop.push_back(v);
+
+        u = parent[u];
+        v = parent[v];
+    }
+    loop.push_back(u);
+
+    graph[edge.first].push_back(edge.second);
+    graph[edge.second].push_back(edge.first);
+
+    vi disa(n, oo);
+    vi disb(n, oo);
+
+    auto bfs = [&](int ini, vi &dis) {
+        dis[ini] = 0;
+        queue<int> q;
+        q.push(ini);
+
+        while (!q.empty()) {
+            auto i = q.front();
+            q.pop();
+
+            repv(j, graph[i]) {
+                if (dis[j] > dis[i] + 1) {
+                    dis[j] = dis[i] + 1;
+                    q.push(j);
+                }
+            }
+        }
+    };
+
+    bfs(a, disa);
+    bfs(b, disb);
+
+    repv(i, loop) {
+        if (disa[i] > disb[i]) {
+            cout << "YES\n";
+            return;
+        }
+    }
+
+    cout << "NO\n";
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 905 (Div. 3)/F. You Are So Beautiful.cpp b/Codeforces Round 905 (Div. 3)/F. You Are So Beautiful.cpp
new file mode 100644
index 0000000..51d49a6
--- /dev/null
+++ b/Codeforces Round 905 (Div. 3)/F. You Are So Beautiful.cpp	
@@ -0,0 +1,157 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1883/F */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+    vl a(n);
+    cin >> a;
+
+    map<ll, int> var;
+    repv(i, a) {
+        var[i] = 0;
+    }
+
+    int v = 0;
+
+    repv(i, var) {
+        i.second = v;
+        v++;
+    }
+
+    repv(i, a) {
+        i = var[i];
+    }
+
+    vi next(n);
+    vi posr(n, -1);
+
+    rep(i, n) {
+        next[n - i - 1] = posr[a[n - i - 1]];
+        posr[a[n - i - 1]] = n - i - 1;
+    }
+
+    ll ans = 0;
+    int c = 0;
+
+    vi posl(n, -1);
+
+    rep(i, n) {
+        if (next[i] != -1) {
+            if (posl[a[i]] == -1) {
+                posl[a[i]] = 1;
+                c++;
+            }
+            continue;
+        }
+
+        if (posl[a[i]] == -1) {
+            posl[a[i]] = 1;
+            c++;
+        }
+
+        ans += c;
+    }
+
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 907 (Div. 2)/C. Smilo and Monsters.cpp b/Codeforces Round 907 (Div. 2)/C. Smilo and Monsters.cpp
new file mode 100644
index 0000000..dac6e72
--- /dev/null
+++ b/Codeforces Round 907 (Div. 2)/C. Smilo and Monsters.cpp	
@@ -0,0 +1,166 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1891/C */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    vl a(n);
+    cin >> a;
+    sortv(a);
+
+    ll x = 0;
+
+    int i = 0;
+    int j = n - 1;
+    ll ans = 0;
+
+    while (i < j) {
+        if (x + a[i] >= a[j]) {
+            ll diff = a[j] - x;
+            a[i] -= diff;
+            a[j] = 0;
+            ans += diff + 1;
+            j--;
+            i += a[i] == 0;
+            x = 0;
+            continue;
+        }
+
+        ans += a[i];
+        x += a[i];
+        a[i] = 0;
+        i++;
+
+        if (x >= a[j]) {
+            ans++;
+            x -= a[j];
+            a[j] = 0;
+            j--;
+        }
+    }
+
+    if (i > j) {
+        cout << ans << '\n';
+        return;
+    }
+
+    ll low = 0;
+    ll high = 1e9;
+    ll act = 0;
+    while (low <= high) {
+        ll mid = (low + high) >> 1;
+
+        if (x + (mid << 1) <= a[i]) {
+            act = mid;
+            low = mid + 1;
+            continue;
+        }
+
+        high = mid - 1;
+    }
+
+    ans += min(a[i], max(a[i] - (act << 1) - x + 1 + act, 0LL));
+
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 911 (Div. 2)/C. Anji's Binary Tree.cpp b/Codeforces Round 911 (Div. 2)/C. Anji's Binary Tree.cpp
new file mode 100644
index 0000000..dea3119
--- /dev/null
+++ b/Codeforces Round 911 (Div. 2)/C. Anji's Binary Tree.cpp	
@@ -0,0 +1,132 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1900/C */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    string a;
+    cin >> a;
+
+    V<array<int, 2>> tree(n);
+
+    rep(i, n) {
+        cin >> tree[i][0] >> tree[i][1];
+        tree[i][0]--;
+        tree[i][1]--;
+    }
+
+    function<int(int)> dfs = [&](int i) -> int {
+        if (i == -1) {
+            return oo;
+        }
+
+        if (tree[i][0] == -1 && tree[i][1] == -1) {
+            return 0;
+        }
+
+        return min(dfs(tree[i][0]) + (a[i] != 'L'), dfs(tree[i][1]) + (a[i] != 'R'));
+    };
+
+    cout << dfs(0) << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 935 (Div. 3)/F. Kirill and Mushrooms.cpp b/Codeforces Round 935 (Div. 3)/F. Kirill and Mushrooms.cpp
new file mode 100644
index 0000000..325683e
--- /dev/null
+++ b/Codeforces Round 935 (Div. 3)/F. Kirill and Mushrooms.cpp	
@@ -0,0 +1,162 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1945/F */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    V<pair<ll, int>> a(n);
+    repv(i, a) {
+        cin >> i.first;
+    }
+
+    ordered_set<pair<int, ll>, greater<>> ord;
+
+    rep(i, n) {
+        int p;
+        cin >> p;
+
+        a[p - 1].second = i;
+        ord.insert({a[p - 1].second, a[p - 1].first});
+    }
+
+    sortv(a);
+
+    ll ans = 0;
+    int count = 0;
+
+    rep(i, n) {
+        ord.erase({a[i].second, a[i].first});
+
+        int low = 0;
+        int high = min((int)ord.size() - 1, a[i].second - 1);
+        int curc = 0;
+        while (low <= high) {
+            int mid = (low + high) >> 1;
+
+            int now = ord.find_by_order(mid)->first;
+            if (now - mid - 1 >= 0) {
+                curc = mid + 1;
+                low = mid + 1;
+                continue;
+            }
+
+            high = mid - 1;
+        }
+
+        curc++;
+        ll curans = a[i].first * curc;
+
+        if (curans > ans) {
+            ans = curans;
+            count = curc;
+            continue;
+        }
+
+        if (ans == curans && count > curc) {
+            count = curc;
+        }
+    }
+
+    cout << ans << ' ' << count << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 937 (Div. 4)/E. Nearly Shortest Repeating Substring.cpp b/Codeforces Round 937 (Div. 4)/E. Nearly Shortest Repeating Substring.cpp
new file mode 100644
index 0000000..8e26faf
--- /dev/null
+++ b/Codeforces Round 937 (Div. 4)/E. Nearly Shortest Repeating Substring.cpp	
@@ -0,0 +1,184 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1950/E */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    string s;
+    cin >> n >> s;
+
+    vi divs;
+
+    auto getdivs = [&]() {
+        for (int i = 1; i * i <= n; i++) {
+            if (n % i == 0) {
+                divs.push_back(i);
+                if (i * i != n) {
+                    divs.push_back(n / i);
+                }
+            }
+        }
+    };
+
+    getdivs();
+    sortv(divs);
+
+    string cur;
+    V<bool> diff;
+    repv(d, divs) {
+        fill(all(diff), false);
+        while (cur.size() < d) {
+            cur.push_back(s[cur.size()]);
+            diff.emplace_back();
+        }
+
+        int j = 0;
+        int c = 0;
+        rep(i, n) {
+            if (cur[j] != s[i]) {
+                diff[j] = true;
+                c++;
+            }
+            j = (j + 1) * (j < d - 1);
+        }
+
+        if (c <= 1) {
+            cout << d << '\n';
+            return;
+        }
+
+        if (c == n / d - 1) {
+            auto check = [&]() {
+                int choice = -1;
+                rep(i, d) {
+                    if (diff[i]) {
+                        if (choice != -1) {
+                            return false;
+                        }
+                        choice = i;
+                    }
+                }
+
+                char prev = cur[choice];
+                cur[choice] = s[choice + d];
+
+                int c = 0;
+                int j = 0;
+                rep(i, n) {
+                    if (cur[j] != s[i]) {
+                        c++;
+                    }
+                    j = (j + 1) * (j < d - 1);
+                }
+
+                cur[choice] = prev;
+
+                return c == 1;
+            };
+
+            if (check()) {
+                cout << d << '\n';
+                return;
+            }
+        }
+    }
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 945 (Div. 2)/B. Cat, Fox and the Lonely Array.cpp b/Codeforces Round 945 (Div. 2)/B. Cat, Fox and the Lonely Array.cpp
new file mode 100644
index 0000000..6e8cbe4
--- /dev/null
+++ b/Codeforces Round 945 (Div. 2)/B. Cat, Fox and the Lonely Array.cpp	
@@ -0,0 +1,157 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1973/B */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    vi a(n);
+    cin >> a;
+
+    int low = 1;
+    int high = n;
+    int ans = n;
+    while (low <= high) {
+        int mid = (low + high) >> 1;
+
+        vi bit(20);
+        rep(i, mid) {
+            rep(j, 20) {
+                bit[j] += (a[i] >> j) & 1;
+            }
+        }
+
+        int now = 0;
+        rep(i, 20) {
+            now |= (bit[i] > 0) << i;
+        }
+
+        bool valid = true;
+        nrep(i, 1, n - mid + 1) {
+            rep(j, 20) {
+                bit[j] -= (a[i - 1] >> j) & 1;
+                bit[j] += (a[i + mid - 1] >> j) & 1;
+            }
+
+            int cur = 0;
+            rep(j, 20) {
+                cur |= (bit[j] > 0) << j;
+            }
+
+            if (cur != now) {
+                valid = false;
+                break;
+            }
+        }
+
+        if (valid) {
+            ans = mid;
+            high = mid - 1;
+            continue;
+        }
+
+        low = mid + 1;
+    }
+
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 954 (Div. 3)/D. Mathematical Problem.cpp b/Codeforces Round 954 (Div. 3)/D. Mathematical Problem.cpp
new file mode 100644
index 0000000..62069d0
--- /dev/null
+++ b/Codeforces Round 954 (Div. 3)/D. Mathematical Problem.cpp	
@@ -0,0 +1,153 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1986/D */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    string s;
+    cin >> s;
+    
+    if (n == 2) {
+        cout << stoi(s) << '\n';
+        return;
+    }
+
+    repv(i, s) {
+        i -= '0';
+    }
+
+    if (n == 3) {
+        int onei = s[0] * 10 + s[1];
+        int twoi = s[2];
+
+        int onej = s[0];
+        int twoj = s[1] * 10 + s[2];
+
+        cout << min({onei + twoi, onei * twoi, onej + twoj, onej * twoj}) << '\n';
+        return;
+    }
+
+    ll total = 0;
+    rep(i, n) {
+        if (s[i] == 0) {
+            cout << "0\n";
+            return;
+        }
+
+        if (s[i] == 1) {
+            continue;
+        }
+
+        total += s[i];
+    }
+
+    ll ans = OO;
+    rep(i, n - 1) {
+        ll act = s[i] * 10 + s[i + 1];
+
+        rmin(ans, total - (s[i] == 1 ? 0 : s[i]) - (s[i + 1] == 1 ? 0 : s[i + 1]) + act);
+    }
+
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 961 (Div. 2)/B2. Bouquet (Hard Version).cpp b/Codeforces Round 961 (Div. 2)/B2. Bouquet (Hard Version).cpp
new file mode 100644
index 0000000..02e3551
--- /dev/null
+++ b/Codeforces Round 961 (Div. 2)/B2. Bouquet (Hard Version).cpp	
@@ -0,0 +1,140 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1995/B2 */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    ll m;
+    cin >> n >> m;
+
+    V<pair<ll, ll>> a(n);
+    repv(i, a) {
+        cin >> i.first;
+    }
+
+    repv(i, a) {
+        cin >> i.second;
+    }
+
+    sortv(a);
+
+    ll ans = 0;
+
+    nrep(i, 1, n) {
+        rmax(ans, min(m / a[i - 1].first, a[i - 1].second) * a[i - 1].first);
+
+        if (a[i - 1].first != a[i].first - 1) {
+            continue;
+        }
+
+        ll c1 = min(a[i - 1].second, m / a[i - 1].first);
+        ll c2 = min(a[i].second, (m - a[i - 1].first * c1) / a[i].first);
+        ll c = m - c1 * a[i - 1].first - c2 * a[i].first;
+        ll r = min({c1, a[i].second - c2, c});
+
+        rmax(ans, (c1 - r) * a[i - 1].first + (c2 + r) * a[i].first);
+    }
+
+    rmax(ans, min(m / a.back().first, a.back().second) * a.back().first);
+
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 968 (Div. 2)/D1. Turtle and a MEX Problem (Easy Version).cpp b/Codeforces Round 968 (Div. 2)/D1. Turtle and a MEX Problem (Easy Version).cpp
new file mode 100644
index 0000000..c384efe
--- /dev/null
+++ b/Codeforces Round 968 (Div. 2)/D1. Turtle and a MEX Problem (Easy Version).cpp	
@@ -0,0 +1,149 @@
+/* Problem URL: https://codeforces.com/problemset/problem/2003/D1 */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+bool b[(int)2e5 + 2];
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    ll m;
+    cin >> n >> m;
+
+    ll maximal = 0;
+
+    rep(i, n) {
+        int l;
+        cin >> l;
+
+        rep(j, l) {
+            int now;
+            cin >> now;
+            if (now > l) {
+                continue;
+            }
+            b[now] = true;
+        }
+
+        ll mex = 0;
+        while (b[mex]) {
+            mex++;
+        }
+
+        mex++;
+        while (b[mex]) {
+            mex++;
+        }
+
+        rmax(maximal, mex);
+
+        rep(j, l + 1) {
+            b[j] = false;
+        }
+    }
+
+    if (maximal >= m) {
+        cout << maximal * (m + 1) << '\n';
+        return;
+    }
+
+    cout << maximal * (maximal + 1) + (m - maximal) * (maximal + m + 1) / 2 << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 984 (Div. 3)/F. XORificator 3000.cpp b/Codeforces Round 984 (Div. 3)/F. XORificator 3000.cpp
new file mode 100644
index 0000000..ac5f532
--- /dev/null
+++ b/Codeforces Round 984 (Div. 3)/F. XORificator 3000.cpp	
@@ -0,0 +1,145 @@
+/* Problem URL: https://codeforces.com/problemset/problem/2036/F */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+ll XOR(ll to)
+{
+    ll ans[] = {to, 1, to + 1, 0};
+    return ans[to & 3];
+}
+
+void solve()
+{
+    ll l, r, i, k;
+    cin >> l >> r >> i >> k;
+
+    ll ans = XOR(r) ^ (l > 0 ? XOR(l - 1) : 0);
+
+    if (r <= (1LL << i)) {
+        cout << (ans ^ (k >= l && k <= r ? k : 0));
+        return;
+    }
+
+    ll lcomp = l >> i;
+    ll rcomp = r >> i;
+
+    if (rcomp > 0) {
+        ans ^= (XOR(rcomp - 1) ^ (lcomp > 0 ? XOR(lcomp - 1) : 0)) << i;
+    }
+
+    if ((rcomp - lcomp) & 1) {
+        ans ^= k;
+    }
+
+    ll mask = 1LL << i;
+
+    if ((l & mask) <= k) {
+        ans ^= k;
+        ans ^= (l & ~mask);
+    }
+
+    if ((r & mask) >= k) {
+        ans ^= k;
+        ans ^= (r & ~mask);
+    }
+
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 986 (Div. 2)/C. Alice's Adventures in Cutting Cake.cpp b/Codeforces Round 986 (Div. 2)/C. Alice's Adventures in Cutting Cake.cpp
new file mode 100644
index 0000000..7362bf0
--- /dev/null
+++ b/Codeforces Round 986 (Div. 2)/C. Alice's Adventures in Cutting Cake.cpp	
@@ -0,0 +1,171 @@
+/* Problem URL: https://codeforces.com/problemset/problem/2028/C */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, m;
+    ll v;
+    cin >> n >> m >> v;
+
+    vl a(n);
+    cin >> a;
+
+    vl pref(n);
+    vl suf(n);
+
+    ll cur = 0;
+    rep(i, n) {
+        cur += a[i];
+        if (cur >= v) {
+            pref[i]++;
+            cur = 0;
+        }
+    }
+
+    cur = 0;
+    for (int i = n - 1; i >= 0; i--) {
+        cur += a[i];
+        if (cur >= v) {
+            suf[i]++;
+            cur = 0;
+        }
+    }
+
+    nrep(i, 1, n) {
+        pref[i] += pref[i - 1];
+        suf[n - i - 1] += suf[n - i];
+    }
+
+    if (pref.back() < m) {
+        cout << "-1\n";
+        return;
+    }
+
+    auto gettot = [&](int l, int r) {
+        ll tot = 0;
+        if (l > 0) {
+            tot += pref[l - 1];
+        }
+
+        if (r < n - 1) {
+            tot += suf[r + 1];
+        }
+
+        return tot;
+    };
+
+    ll ans = 0;
+    cur = 0;
+    int j = 0;
+    rep(i, n) {
+        cur += a[i];
+
+        while (gettot(j, i) < m) {
+            cur -= a[j];
+            j++;
+        }
+
+        rmax(ans, cur);
+    }
+    
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Codeforces Round 991 (Div. 3)/F. Maximum modulo equality.cpp b/Codeforces Round 991 (Div. 3)/F. Maximum modulo equality.cpp
index 15cab1c..597b6c3 100644
--- a/Codeforces Round 991 (Div. 3)/F. Maximum modulo equality.cpp	
+++ b/Codeforces Round 991 (Div. 3)/F. Maximum modulo equality.cpp	
@@ -1,16 +1,22 @@
-/* Problem URL: https://codeforces.com/contest/2050/problem/F */
+/* Problem URL: https://codeforces.com/problemset/problem/2050/F */
 
 #include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
 
 using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
 
 #define V vector
 
 #define rmin(a, b) a = min(a, b)
 #define rmax(a, b) a = max(a, b)
 
-#define rep(i, lim) for (size_t i = 0; i < (lim); i++)
-#define nrep(i, s, lim) for (size_t i = s; i < (lim); i++)
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
 
 #define repv(i, v) for (auto &i : (v))
 #define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
@@ -69,25 +75,70 @@ auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
     return is;
 }
 
-int dp(int i, int j, int k, string &a, string &b, string &c)
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
 {
-    if (i >= a.size() || j >= b.size() || k >= c.size()) {
-        return 0;
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, q;
+    cin >> n >> q;
+
+    vl a(n);
+    cin >> a;
+
+    if (n == 1) {
+        while (q--) {
+            int l, r;
+            cin >> l >> r;
+            cout << "0" << " \n"[q == 0];
+        }
+        return;
     }
 
-    if (a[i] != c[k] && b[j] != c[k]) {
-        return min(dp(i + 1, j, k + 1, a, b, c), dp(i, j + 1, k, a, b, c)) + 1;
+    vl diffs(n - 1);
+    rep(i, n - 1) {
+        diffs[i] = abs(a[i] - a[i + 1]);
     }
 
-    if (a[i] == b[j]) {
-        return min(dp(i + 1, j, k + 1, a, b, c), dp(i, j + 1, k, a, b, c));
+    int size = n - 1;
+
+    vvl sparse(20, vl(size));
+
+    rep(i, size) {
+        sparse[0][i] = diffs[i];
     }
 
-    if (a[i] == c[k]) {
-        return dp(i + 1, j, k + 1, a, b, c);
+    nrep(j, 1, 20) {
+        for (int i = 0; i + (1 << (j - 1)) < size; i++) {
+            sparse[j][i] = __gcd(sparse[j - 1][i], sparse[j - 1][i + (1 << (j - 1))]);
+        }
     }
 
-    return dp(i, j + 1, k + 1, a, b, c);
+    auto squery = [&](int l, int r) {
+        int log = 31 - __builtin_clz(r - l + 1);
+        return __gcd(sparse[log][l], sparse[log][r - (1 << log) + 1]);
+    };
+
+    while (q--) {
+        int l, r;
+        cin >> l >> r;
+        l--, r--;
+
+        if (l == r) {
+            cout << "0" << " \n"[q == 0];
+            continue;
+        }
+
+        cout << squery(l, r - 1) << " \n"[q == 0];
+    }
 }
 
 int main()
@@ -95,12 +146,11 @@ int main()
     ios::sync_with_stdio(false);
     cin.tie(nullptr);
 
-    int t;
-    cin >> t;
-    while (t--) {
-        string a, b, c;
-        cin >> a >> b >> c;
+    pre();
 
-        cout << dp(0, 0, 0, a, b, c) << '\n';
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
     }
 }
diff --git a/Codeforces Round 994 (Div. 2)/C. MEX Cycle.cpp b/Codeforces Round 994 (Div. 2)/C. MEX Cycle.cpp
new file mode 100644
index 0000000..913afd1
--- /dev/null
+++ b/Codeforces Round 994 (Div. 2)/C. MEX Cycle.cpp	
@@ -0,0 +1,152 @@
+/* Problem URL: https://codeforces.com/problemset/problem/2049/C */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, x, y;
+    cin >> n >> x >> y;
+    x--, y--;
+
+    vi ans(n, -1);
+    ans[x] = 0;
+    ans[y] = 1;
+
+    queue<int> q;
+    q.push(x - 1 + n * (x == 0));
+    q.push(x + 1 - n * (x == n - 1));
+    q.push(y - 1 + n * (y == 0));
+    q.push(y + 1 - n * (y == n - 1));
+
+    while (!q.empty()) {
+        auto i = q.front();
+        q.pop();
+
+        if (ans[i] != -1) {
+            continue;
+        }
+
+        int prev = i - 1 + n * (i == 0);
+        int next = i + 1 - n * (i == n - 1);
+
+        array<bool, 6> ex = {};
+        
+        if (ans[prev] != -1) {
+            ex[ans[prev]] = true;
+        }
+
+        if (ans[next] != -1) {
+            ex[ans[next]] = true;
+        }
+
+        int mex = 0;
+        while (ex[mex]) {
+            mex++;
+        }
+
+        ans[i] = mex;
+
+        q.push(prev);
+        q.push(next);
+    }
+
+    cout << ans;
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Educational Codeforces Round 137 (Rated for Div. 2)/D. Problem with Random Tests.cpp b/Educational Codeforces Round 137 (Rated for Div. 2)/D. Problem with Random Tests.cpp
new file mode 100644
index 0000000..615ae5d
--- /dev/null
+++ b/Educational Codeforces Round 137 (Rated for Div. 2)/D. Problem with Random Tests.cpp	
@@ -0,0 +1,155 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1743/D */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 0
+
+void solve()
+{
+    int n;
+    string s;
+    cin >> n >> s;
+
+    int ind = 0;
+    while (ind < s.size() && s[ind] == '0') {
+        ind++;
+    }
+
+    if (ind >= s.size()) {
+        cout << "0\n";
+        return;
+    }
+
+    // s = s.substr(ind);
+
+    while (ind < s.size() && s[ind] == '1') {
+        ind++;
+    }
+
+    if (ind == s.size()) {
+        cout << s << '\n';
+        return;
+    }
+
+    int size = s.size() - ind;
+    string ans = s;
+
+    while (size < s.size()) {
+        for (int i = 0; i + size < s.size(); i++) {
+            string cur = s.substr(i, size);
+            string tmp = s;
+
+            rep(j, size) {
+                if (cur[size - j - 1] == '1') {
+                    tmp[s.size() - j - 1] = '1';
+                }
+            }
+
+            rmax(ans, tmp);
+        }
+        size++;
+    }
+
+    int c = 0;
+    while (ans[c] == '0') {
+        c++;
+    }
+
+    cout << ans.substr(c) << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Educational Codeforces Round 145 (Rated for Div. 2)/C. Sum on Subarrays.cpp b/Educational Codeforces Round 145 (Rated for Div. 2)/C. Sum on Subarrays.cpp
new file mode 100644
index 0000000..00e6026
--- /dev/null
+++ b/Educational Codeforces Round 145 (Rated for Div. 2)/C. Sum on Subarrays.cpp	
@@ -0,0 +1,131 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1809/C */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, k;
+    cin >> n >> k;
+
+    vi ans(n, -2);
+
+    vi pos(n);
+    rep(i, n) {
+        if (~i & 1) {
+            pos[i] = i >> 1;
+        } else {
+            pos[i] = n - (i >> 1) - 1;
+        }
+    }
+
+    for (int cur = 0; k > 0; cur++) {
+        k--;
+        if (k == 0) {
+            ans[pos[cur]] = 1;
+            continue;
+        }
+        int now = min(n - cur - 1, k);
+        ans[pos[cur]] = now * 2 + 1;
+        k -= now;
+    }
+
+    cout << ans;
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Educational Codeforces Round 146 (Rated for Div. 2)/B. Long Legs.cpp b/Educational Codeforces Round 146 (Rated for Div. 2)/B. Long Legs.cpp
new file mode 100644
index 0000000..b089455
--- /dev/null
+++ b/Educational Codeforces Round 146 (Rated for Div. 2)/B. Long Legs.cpp	
@@ -0,0 +1,119 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1814/B */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    ll a, b;
+    cin >> a >> b;
+
+    auto calc = [&](ll now) {
+        return now - 1 + (a + now - 1) / now + (b + now - 1) / now;
+    };
+
+    ll ans = OO;
+
+    nrep(i, 1, (int)1e5 + 1) {
+        rmin(ans, calc(i));
+    }
+
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Educational Codeforces Round 146 (Rated for Div. 2)/C. Search in Parallel.cpp b/Educational Codeforces Round 146 (Rated for Div. 2)/C. Search in Parallel.cpp
new file mode 100644
index 0000000..53481bd
--- /dev/null
+++ b/Educational Codeforces Round 146 (Rated for Div. 2)/C. Search in Parallel.cpp	
@@ -0,0 +1,147 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1814/C */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    ll s1, s2;
+    cin >> n >> s1 >> s2;
+
+    V<pair<int, int>> ball(n);
+    rep(i, n) {
+        cin >> ball[i].first;
+        ball[i].second = i + 1;
+    }
+
+    sort(all(ball), greater<>());
+
+    vi a;
+    vi b;
+
+    int now = 0;
+    ll rb1 = s1;
+    ll rb2 = s2;
+    while (now < n) {
+        if (rb1 <= rb2) {
+            a.push_back(ball[now].second);
+            now++;
+            rb1 += s1;
+            continue;
+        }
+
+        b.push_back(ball[now].second);
+        now++;
+        rb2 += s2;
+    }
+
+    cout << a.size();
+    rep(i, a.size()) {
+        cout << ' ' << a[i];
+    }
+    cout << '\n';
+
+    cout << b.size();
+    rep(i, b.size()) {
+        cout << ' ' << b[i];
+    }
+    cout << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Educational Codeforces Round 147 (Rated for Div. 2)/D. Black Cells.cpp b/Educational Codeforces Round 147 (Rated for Div. 2)/D. Black Cells.cpp
new file mode 100644
index 0000000..288ba25
--- /dev/null
+++ b/Educational Codeforces Round 147 (Rated for Div. 2)/D. Black Cells.cpp	
@@ -0,0 +1,137 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1821/D */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    ll k;
+    cin >> n >> k;
+
+    V<pair<ll, ll>> ed(n);
+    repv(i, ed) {
+        cin >> i.first;
+    }
+
+    repv(i, ed) {
+        cin >> i.second;
+    }
+
+    ll ans = OO;
+    ll total = 0;
+
+    priority_queue<ll, vl, greater<>> pq;
+    rep(i, n) {
+        ll cost = ed[i].second - ed[i].first + 1;
+        pq.push(cost);
+        total += cost;
+        while (total - pq.top() >= k && pq.top() == 1) {
+            total -= pq.top();
+            pq.pop();
+        }
+
+        if (total >= k) {
+            rmin(ans, ed[i].second - total + k + (ll)pq.size() * 2);
+        }
+    }
+    
+    cout << (ans == OO ? -1 : ans) << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Educational Codeforces Round 151 (Rated for Div. 2)/C. Strong Password.cpp b/Educational Codeforces Round 151 (Rated for Div. 2)/C. Strong Password.cpp
new file mode 100644
index 0000000..7a8f251
--- /dev/null
+++ b/Educational Codeforces Round 151 (Rated for Div. 2)/C. Strong Password.cpp	
@@ -0,0 +1,152 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1845/C */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    string s, l, r;
+    int m;
+
+    cin >> s >> m >> l >> r;
+
+    vvi next(s.size() + 1);
+    vi prev(10, s.size() + 1);
+
+    for (int i = s.size() - 1; i >= 0; i--) {
+        next[i + 1] = prev;
+        prev[s[i] - '0'] = i + 1;
+    }
+    next[0] = prev;
+
+    rep(i, m) {
+        l[i] -= '0';
+        r[i] -= '0';
+    }
+
+    vvi memo(s.size() + 1, vi(m, -1));
+
+    function<bool(int, int)> dp = [&](int i, int j) {
+        if (i > s.size()) {
+            return true;
+        }
+        
+        if (j >= m) {
+            return false;
+        }
+
+        int &ans = memo[i][j];
+        if (ans != -1) {
+            return false;
+        }
+
+        ans = 0;
+
+        nrep(k, l[j], r[j] + 1) {
+            if (dp(next[i][k], j + 1)) {
+                return true;
+            }
+        }
+
+        return false;
+    };
+
+    cout << (dp(0, 0) ? "YES\n" : "NO\n");
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Educational Codeforces Round 155 (Rated for Div. 2)/C. Make it Alternating.cpp b/Educational Codeforces Round 155 (Rated for Div. 2)/C. Make it Alternating.cpp
new file mode 100644
index 0000000..a03b46e
--- /dev/null
+++ b/Educational Codeforces Round 155 (Rated for Div. 2)/C. Make it Alternating.cpp	
@@ -0,0 +1,163 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1879/C */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+const int MAXN = 2e5 + 1;
+const ll mod = 998244353;
+ll fact[MAXN];
+ll inv[MAXN];
+
+void pre()
+{
+    fact[0] = 1;
+    nrep(i, 1, MAXN) {
+        fact[i] = (fact[i - 1] * i) % mod;
+    }
+
+    inv[0] = 1;
+    inv[1] = 1;
+    nrep(i, 2, MAXN) {
+        inv[i] = (mod - mod / i) * inv[mod % i] % mod;
+    }
+
+    nrep(i, 2, MAXN) {
+        inv[i] = (inv[i] * inv[i - 1]) % mod;
+    }
+}
+
+#define TEST 1
+
+void solve()
+{
+    string s;
+    cin >> s;
+
+    vl count;
+    int now = 1;
+    ll total = 0;
+    int c = s.size() - 1;
+
+    nrep(i, 1, s.size()) {
+        if (s[i] == s[i - 1]) {
+            now++;
+            continue;
+        }
+
+        c--;
+
+        if (now > 1) {
+            count.push_back(now);
+            total += now - 1;
+        }
+
+        now = 1;
+    }
+
+    if (now > 1) {
+        total += now - 1;
+        count.push_back(now);
+    }
+
+    auto comb = [&](ll n, ll k) {
+        return (fact[n] * inv[k] % mod * inv[n - k]) % mod;
+    };
+
+    ll ans = 1;
+    repv(i, count) {
+        ans = (ans * fact[i]) % mod;
+        ans = (ans * comb(total, i - 1)) % mod;
+        total -= i - 1;
+    }
+
+    cout << c << ' ' << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Educational Codeforces Round 171 (Rated for Div. 2)/C. Action Figures.cpp b/Educational Codeforces Round 171 (Rated for Div. 2)/C. Action Figures.cpp
new file mode 100644
index 0000000..909ee9f
--- /dev/null
+++ b/Educational Codeforces Round 171 (Rated for Div. 2)/C. Action Figures.cpp	
@@ -0,0 +1,133 @@
+/* Problem URL: https://codeforces.com/problemset/problem/2026/C */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    string a;
+    cin >> n >> a;
+
+    ll ans = 0;
+    priority_queue<ll> ac;
+    for (int i = n - 1; i >= 0; i--) {
+        if (a[i] == '0') {
+            if (!ac.empty()) {
+                ans -= ac.top();
+                ac.pop();
+            }
+
+            ans += i + 1;
+            continue;
+        }
+
+        ans += i + 1;
+        ac.push(i + 1);
+    }
+
+    int rem = ac.size() >> 1;
+    while (rem--) {
+        ans -= ac.top();
+        ac.pop();
+    }
+
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Educational Codeforces Round 171 (Rated for Div. 2)/D. Sums of Segments.cpp b/Educational Codeforces Round 171 (Rated for Div. 2)/D. Sums of Segments.cpp
new file mode 100644
index 0000000..d1bce0f
--- /dev/null
+++ b/Educational Codeforces Round 171 (Rated for Div. 2)/D. Sums of Segments.cpp	
@@ -0,0 +1,173 @@
+/* Problem URL: https://codeforces.com/problemset/problem/2026/D */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 0
+
+void solve()
+{
+    int n;
+    cin >> n;
+    vl a(n);
+    cin >> a;
+
+    vl pref(n + 1);
+    vl preft(n + 1);
+
+    rep(i, n) {
+        pref[i + 1] = pref[i] + a[i];
+    }
+
+    rep(i, n) {
+        preft[i + 1] = pref.back() - pref[i] + preft[i];
+    }
+
+    // cout << preft;
+
+    ll total = (ll)n * (n + 1) / 2;
+
+    int q;
+    cin >> q;
+    while (q--) {
+        ll l, r;
+        cin >> l >> r;
+        l--, r--;
+
+        ll low = 0;
+        ll high = n;
+        ll lans = 0;
+        while (low <= high) {
+            ll mid = (low + high) >> 1;
+
+            if (mid * (n + mid) / 2 <= l) {
+                lans = mid;
+                low = mid + 1;
+                continue;
+            }
+
+            high = mid - 1;
+        }
+
+        l -= lans * (lans + n) / 2;
+
+        low = 0;
+        high = n;
+        ll rans = 0;
+        while (low <= high) {
+            ll mid = (low + high) >> 1;
+
+            if (mid * (n + mid) / 2 <= r) {
+                rans = mid;
+                low = mid + 1;
+                continue;
+            }
+
+            high = mid - 1;
+        }
+
+        r -= rans * (rans + n) / 2;
+
+        if (rans == lans) {
+            cout << pref[rans + r + 1] - pref[lans + l] << '\n';
+            continue;
+        }
+
+        cout << preft[rans] - preft[lans] << '\n';
+    }
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/ITMO Academy: pilot course - Suffix Array - Step 1/A. Suffix Array - 1.cpp b/ITMO Academy: pilot course - Suffix Array - Step 1/A. Suffix Array - 1.cpp
new file mode 100644
index 0000000..a12039a
--- /dev/null
+++ b/ITMO Academy: pilot course - Suffix Array - Step 1/A. Suffix Array - 1.cpp	
@@ -0,0 +1,173 @@
+/* Problem URL: https://codeforces.com/edu/course/2/lesson/2/1/practice/contest/269100/problem/A */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 0
+
+void solve()
+{
+    string a;
+    cin >> a;
+
+    a.push_back('$');
+
+    int n = a.size();
+
+    int log = 1;
+    if (n > 1) {
+        log = 32 - __builtin_clz(n - 1);
+    }
+
+    vvi suffix(log + 1, vi(n));
+    rep(i, n) {
+        suffix[0][i] = i;
+    }
+
+    sort(all(suffix[0]), [&](int i, int j){
+         return a[i] < a[j];
+         });
+
+    vi prev(n);
+    nrep(i, 1, n) {
+        if (a[suffix[0][i]] == a[suffix[0][i - 1]]) {
+            prev[suffix[0][i]] = prev[suffix[0][i - 1]];
+            continue;
+        }
+
+        prev[suffix[0][i]] = prev[suffix[0][i - 1]] + 1;
+    }
+
+    V<tuple<int, int, int>> cur(n);
+
+    nrep(j, 1, log + 1) {
+        rep(i, n) {
+            int next = (i + (1 << (j - 1))) - n * ((i + (1 << (j - 1))) >= n);
+
+            cur[i] = {prev[i], prev[next], i};
+        }
+
+        sort(all(cur), [&](tuple<int, int, int> &a, tuple<int, int, int> &b){
+             auto [ai, aj, ak] = a;
+             auto [bi, bj, bk] = b;
+
+             if (ai == bi) {
+                return aj < bj;
+             }
+             return ai < bi;
+             });
+
+        prev[get<2>(cur[0])] = 0;
+        suffix[j][0] = get<2>(cur[0]);
+        nrep(i, 1, n) {
+            auto [ai, aj, ak] = cur[i];
+            auto [bi, bj, bk] = cur[i - 1];
+
+            suffix[j][i] = ak;
+
+            if (ai == bi && aj == bj) {
+                prev[ak] = prev[bk];
+                continue;
+            }
+
+            prev[ak] = prev[bk] + 1;
+        }
+    }
+
+    cout << suffix[log];
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Pinely Round 4 (Div. 1 + Div. 2)/C. Absolute Zero.cpp b/Pinely Round 4 (Div. 1 + Div. 2)/C. Absolute Zero.cpp
new file mode 100644
index 0000000..b5d2553
--- /dev/null
+++ b/Pinely Round 4 (Div. 1 + Div. 2)/C. Absolute Zero.cpp	
@@ -0,0 +1,140 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1991/C */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n;
+    cin >> n;
+    vl a(n);
+    cin >> a;
+
+    bool act[2] = {false, false};
+
+    rep(i, n) {
+        act[a[i] & 1] = true;
+    }
+
+    if (act[0] && act[1]) {
+        cout << "-1\n";
+        return;
+    }
+
+    vl ops;
+    
+    auto sub = [&](ll now) {
+        ops.push_back(now);
+        rep(i, n) {
+            a[i] = abs(a[i] - now);
+        }
+    };
+
+    rep(i, 30) {
+        sub(1 << (29 - i));
+    }
+
+    if (a[0] == 1) {
+        ops.push_back(1);
+    }
+
+    cout << ops.size() << '\n';
+    cout << ops;
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/Polynomial Round 2022 (Div. 1 + Div. 2, Rated, Prizes!)/B. Coloring.cpp b/Polynomial Round 2022 (Div. 1 + Div. 2, Rated, Prizes!)/B. Coloring.cpp
new file mode 100644
index 0000000..e885717
--- /dev/null
+++ b/Polynomial Round 2022 (Div. 1 + Div. 2, Rated, Prizes!)/B. Coloring.cpp	
@@ -0,0 +1,131 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1774/B */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    ll n, m, k;
+    cin >> n >> m >> k;
+
+    vl a(m);
+    cin >> a;
+
+    if (k == 1) {
+        cout << "YES\n";
+        return;
+    }
+
+    ll lim = n / k;
+    ll mod = n % k;
+
+    rep(i, m) {
+        if (a[i] > lim) {
+            if (a[i] == lim + 1 && mod) {
+                mod--;
+                continue;
+            }
+            cout << "NO\n";
+            return;
+        }
+    }
+
+    cout << "YES\n";
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/TODO.md b/TODO.md
index 2c2b32f..271ad6a 100644
--- a/TODO.md
+++ b/TODO.md
@@ -13,58 +13,79 @@ Official divs from codeforces
 
 - Educational
 
-	1. [F. Frogs and Mosquitoes](https://codeforces.com/contest/609/problem/F)
+	- [ ] [F. Frogs and Mosquitoes](https://codeforces.com/contest/609/problem/F)
 
 		I have no clue where to even start.
 
-	2. [E. Water Taps](https://codeforces.com/contest/954/problem/E)
+	- [ ] [E. Water Taps](https://codeforces.com/contest/954/problem/E)
 
 		I have an idea, but it's really annoying to solve it.
 
-	3. [F. Fibonacci String Subsequences](https://codeforces.com/contest/946/problem/F)
+	- [ ] [F. Fibonacci String Subsequences](https://codeforces.com/contest/946/problem/F)
 
 		Obviously DP, but not sure how to do it...
 
-	4. [F. Imbalance Value of Tree](https://codeforces.com/contest/915/problem/F)
+	- [ ] [F. Imbalance Value of Tree](https://codeforces.com/contest/915/problem/F)
 
 		Tree problem, looks interesting.
 
-	5. [F. Clear The Matrix](https://codeforces.com/contest/903/problem/F)
+	- [ ] [F. Clear The Matrix](https://codeforces.com/contest/903/problem/F)
 
 		DP with optimization?
 
+	- [ ] [D. Sums of Segments](https://codeforces.com/problemset/problem/2026/D)
+
+		Another problem that I didn't have time to finish...
+
 - Div 1/2
 
-	1. [D. Division Versus Addition](https://codeforces.com/contest/2152/problem/D)
+	- [ ] [D. Division Versus Addition](https://codeforces.com/contest/2152/problem/D)
 
 		The idea is simple, but I have to think through it better.
 
-	2. [D2. Inversion Graph Coloring](https://codeforces.com/contest/2143/problem/D2)
+	- [ ] [D2. Inversion Graph Coloring](https://codeforces.com/contest/2143/problem/D2)
 
 		DP with optimization.
 
-	3. [E. Yet Another MEX Problem](https://codeforces.com/contest/2146/problem/E)
+	- [ ] [E. Yet Another MEX Problem](https://codeforces.com/contest/2146/problem/E)
 
 		Maybe MEX with two pointers?	
 
-	4. [D. A Cruel Segment's Thesis](https://codeforces.com/contest/2140/problem/D)
+	- [ ] [D. A Cruel Segment's Thesis](https://codeforces.com/contest/2140/problem/D)
 
 		Looks greedy.
 
-	5. [F. Flint and Steel](https://codeforces.com/contest/2133/problem/F)
+	- [ ] [F. Flint and Steel](https://codeforces.com/contest/2133/problem/F)
 
 		I tried this a long time ago, don't remember what it's about, just remembered
 		that I tried a greedy solution and it didn't work.
+	
+	- [ ] [C. Music Festival](https://codeforces.com/problemset/problem/1801/C)
+
+		Looks like DP.
+	
+	- [ ] [C1. Maple and Tree Beauty (Easy Version)](https://codeforces.com/problemset/problem/2138/C1)
+
+		I finished with one type of knapsack, but apparently there's a better way to do
+		it that's going to be used to optimize later.
+	
+	- [ ] [D1. Hot Start Up (easy version)](https://codeforces.com/contest/1799/problem/D1)
+
+		DP, but couldn't do during the simulation...
 
 - Div 3
 
-	1. [G. Cry Me a River](https://codeforces.com/contest/2137/problem/G)
+	- [ ] [G. Cry Me a River](https://codeforces.com/contest/2137/problem/G)
 
 		Graph problem, don't remember the details.
+	
+	- [ ] [XORificator 3000](https://codeforces.com/problemset/problem/2036/F)
+
+		I had an idea, but didn't have time to implement it.
 
 - Div 4
 
-	1. [F. Gravity Falls](https://codeforces.com/contest/2148/problem/F)
+	- [ ] [F. Gravity Falls](https://codeforces.com/contest/2148/problem/F)
 
 		I barely read it, not sure were I found it either, but looks pretty easy.
 
@@ -74,7 +95,7 @@ Gym from simulations or contests that I did
 
 - ICPC Brazil first phase
 
-	1. [D. Dominoes](https://codeforces.com/gym/106073/problem/D)
+	- [ ] [D. Dominoes](https://codeforces.com/gym/106073/problem/D)
 
 		If I did this one, I would have passed into second phase, must try to solve it
 		ASAP.
@@ -83,22 +104,28 @@ Gym from simulations or contests that I did
 
 	[Link](https://codeforces.com/gym/104875) because it has no problem page in gym.
 
-	1. L. Last Guess
+	- [ ] L. Last Guess
 
 		I think I can solve it with flow.
 
 - USP Try-outs
 
-	1. [B. Tuk-Tuk Express](https://codeforces.com/gym/103934/problem/B)
+	- [ ] [B. Tuk-Tuk Express](https://codeforces.com/gym/103934/problem/B)
 
 		I have NO clue why my code keeps getting WA, awful implementation problem.
 
-	2. [J. Apep, the Lord of Chaos](https://codeforces.com/gym/103934/problem/J)
+	- [ ] [J. Apep, the Lord of Chaos](https://codeforces.com/gym/103934/problem/J)
 
 		I don't remember what the problem was about, I just know that I tried it before.
 
+- think-cell round 1
+
+	- [X] [C. Lexicographically Largest](https://codeforces.com/problemset/problem/1930/C)
+		
+		I'll be honest, I just got bored in the middle.
+
 ## Atcoder
 
-1. [F. Operate K](https://atcoder.jp/contests/abc386/tasks/abc386_f)
+- [ ] [F. Operate K](https://atcoder.jp/contests/abc386/tasks/abc386_f)
 
 	DP with optimization.
diff --git a/TypeDB Forces 2023 (Div. 1 + Div. 2, Rated, Prizes!)/D. Game on Axis.cpp b/TypeDB Forces 2023 (Div. 1 + Div. 2, Rated, Prizes!)/D. Game on Axis.cpp
new file mode 100644
index 0000000..3f3a5d6
--- /dev/null
+++ b/TypeDB Forces 2023 (Div. 1 + Div. 2, Rated, Prizes!)/D. Game on Axis.cpp	
@@ -0,0 +1,229 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1787/D */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+const int MAXN = 2e5 + 10;
+bool vis[MAXN];
+bool frame[MAXN];
+bool loop[MAXN];
+int sz[MAXN];
+
+void solve()
+{
+    int n;
+    cin >> n;
+    vi a(n);
+    cin >> a;
+
+    rep(i, n) {
+        a[i] += i;
+    }
+
+    vi next(n + 2);
+
+    rep(i, n) {
+        int ind = a[i];
+        if (ind < 0) {
+            next[i + 1] = 0;
+            continue;
+        }
+
+        if (ind >= n) {
+            next[i + 1] = n + 1;
+            continue;
+        }
+
+        next[i + 1] = ind + 1;
+    }
+
+    fill(vis, vis + n + 2, false);
+    fill(frame, frame + n + 2, false);
+    fill(loop, loop + n + 2, false);
+
+    ll c = 0;
+
+    function<bool(int)> dfs = [&](int i) -> bool {
+        if (i == 0 || i == n + 1) {
+            return false;
+        }
+
+        vis[i] = true;
+        frame[i] = true;
+
+        int j = next[i];
+        if (frame[j] || loop[j]) {
+            loop[i] = true;
+        }
+
+        if (!vis[j] && dfs(j)) {
+            loop[i] = true;
+        }
+
+        frame[i] = false;
+        c += !loop[i];
+        return loop[i];
+    };
+
+    rep(i, n) {
+        if (!vis[i + 1]) {
+            dfs(i + 1);
+        }
+    }
+    
+    stack<int> topsort;
+    fill(vis, vis + n + 2, false);
+
+    function<void(int)> ss = [&](int i) {
+        if (i == 0 || i == n + 1) {
+            return;
+        }
+
+        vis[i] = true;
+
+        if (!vis[next[i]]) {
+            ss(next[i]);
+        }
+
+        topsort.push(i);
+    };
+
+    rep(i, n) {
+        if (!vis[i + 1] && !loop[i + 1]) {
+            ss(i + 1);
+        }
+    }
+
+    fill(sz, sz + n + 2, 1);
+
+    while (!topsort.empty()) {
+        auto i = topsort.top();
+        topsort.pop();
+
+        sz[next[i]] += sz[i];
+    }
+
+    if (loop[1]) {
+        ll ans = c + n + 1;
+        int now = next[1];
+        fill(frame, frame + n + 2, false);
+        frame[1] = true;
+        while (!frame[now]) {
+            ans += c + n + 1;
+            frame[now] = true;
+            now = next[now];
+        }
+        cout << ans << '\n';
+        return;
+    }
+
+    ll ans = c - sz[1] + n + 1;
+    int now = next[1];
+    ll count = 1;
+    while (now != n + 1 && now != 0) {
+        ans += c - sz[now] + n + 1;
+        count++;
+        now = next[now];
+    }
+
+    ans += (n - count) * 2 * n + (n - count);
+    
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}
diff --git a/think-cell Round 1/C. Lexicographically Largest.cpp b/think-cell Round 1/C. Lexicographically Largest.cpp
new file mode 100644
index 0000000..dae484f
--- /dev/null
+++ b/think-cell Round 1/C. Lexicographically Largest.cpp	
@@ -0,0 +1,212 @@
+/* Problem URL: https://codeforces.com/problemset/problem/1930/C */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+struct dymseg {
+    struct node {
+        int left;
+        int right;
+        int val;
+    };
+
+    V<node> seg;
+
+    dymseg(int n) {
+        seg.emplace_back(-1, -1, 0);
+    }
+
+    int create_node() {
+        seg.emplace_back(-1, -1, 0);
+        return seg.size() - 1;
+    }
+
+    void create_nodes(int i) {
+        if (seg[i].left == -1) {
+            seg[i].left = create_node();
+        }
+
+        if (seg[i].right == -1) {
+            seg[i].right = create_node();
+        }
+    }
+
+    void update(int i, ll l, ll r, int p) {
+        if (l == r) {
+            seg[i].val = 1;
+            return;
+        }
+        
+        seg[i].val++;
+
+        create_nodes(i);
+
+        ll mid = (l + r) >> 1;
+
+        if (mid >= p) {
+            update(seg[i].left, l, mid, p);
+            return;
+        }
+
+        update(seg[i].right, mid + 1, r, p);
+    }
+
+    ll tl, tr;
+
+    ll query(int i, ll l, ll r) {
+        if (l > tr || r < tl || seg[i].val == r - l + 1) {
+            return -1;
+        }
+
+        if (l == r) {
+            return l;
+        }
+
+        ll mid = (l + r) >> 1;
+        
+        create_nodes(i);
+
+        int ans = query(seg[i].right, mid + 1, r);
+
+        if (ans != -1) {
+            return ans;
+        }
+
+        return query(seg[i].left, l, mid);
+    }
+
+    public:
+    void update(ll p) {
+        update(0, 0, 1LL << 31, p);
+    }
+
+    ll query(ll l, ll r) {
+        tl = l;
+        tr = r;
+        return query(0, 0, 1LL << 31);
+    }
+};
+
+void solve()
+{
+    int n;
+    cin >> n;
+
+    vl a(n);
+    cin >> a;
+
+    dymseg seg(n);
+
+    set<ll, greater<>> ans;
+    rep(i, n) {
+        ll choice = seg.query(a[i], a[i] + i + 1);
+        if (choice == -1) {
+            continue;
+        }
+
+        ans.insert(choice);
+        seg.update(choice);
+    }
+
+    repv(i, ans) {
+        cout << i << ' ';
+    }
+    cout << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}