Add a lot more of my solutions.

I don't remember which ones doesn't pass though

CSES Problem Set/Planets Queries II.cpp

@@ -0,0 +1,240 @@
+/* Problem URL: https://cses.fi/problemset/task/1160 */
+
+#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 n, q;
+    cin >> n >> q;
+
+    vi parent(n);
+    rep(i, n) {
+        int a;
+        cin >> a;
+
+        parent[i] = a - 1;
+    }
+
+    V<bool> loop(n);
+    vi group(n);
+    vi cyclepos(n);
+
+    V<bool> vis(n);
+    V<bool> frame(n);
+    vi groupsize;
+    vi cyclechoice(n);
+    int g = 0;
+
+    auto func = [&](int i) {
+        set<int> used;
+        while (!vis[i] && !frame[i]) {
+            vis[i] = true;
+            frame[i] = true;
+            used.insert(i);
+            i = parent[i];
+        }
+
+        if (frame[i]) {
+            loop[i] = true;
+            group[i] = g;
+            cyclechoice[i] = i;
+
+            int now = 1;
+
+            int j = parent[i];
+
+            while (j != i) {
+                cyclepos[j] = now;
+                now++;
+                loop[j] = true;
+                group[j] = g;
+                cyclechoice[j] = j;
+                j = parent[j];
+            }
+
+            g++;
+            groupsize.push_back(now);
+        }
+
+        for (auto j : used) {
+            frame[j] = false;
+        }
+    };
+
+    rep(i, n) {
+        if (vis[i]) {
+            continue;
+        }
+
+        func(i);
+    }
+
+    fill(all(vis), false);
+    vi pos(n);
+
+    function<void(int)> dfs = [&](int i) {
+        vis[i] = true;
+
+        if (!vis[parent[i]] && !loop[parent[i]]) {
+            dfs(parent[i]);
+        }
+
+        pos[i] = pos[parent[i]] + 1;
+        cyclechoice[i] = cyclechoice[parent[i]];
+    };
+
+    rep(i, n) {
+        if (!loop[i] && !vis[i]) {
+            dfs(i);
+        }
+    }
+
+    vvi lift(17, vi(n));
+
+    vi valids;
+    rep(i, n) {
+        if (!loop[i]) {
+            valids.push_back(i);
+            lift[0][i] = parent[i];
+        }
+    }
+
+    nrep(i, 1, 17) {
+        repv(j, valids) {
+            lift[i][j] = lift[i - 1][lift[i - 1][j]];
+        }
+    }
+
+    while (q--) {
+        int a, b;
+        cin >> a >> b;
+        a--, b--;
+
+        if (loop[a] && loop[b]) {
+            if (group[a] != group[b]) {
+                cout << "-1\n";
+                continue;
+            }
+
+            int g = group[a];
+
+            cout << ((cyclepos[b] - cyclepos[a]) % groupsize[g] + groupsize[g]) % groupsize[g] << '\n';
+            continue;
+        }
+
+        if (loop[a] && !loop[b]) {
+            cout << "-1\n";
+            continue;
+        }
+
+        if (!loop[a] && loop[b]) {
+            int choice = cyclechoice[a];
+
+            if (group[choice] != group[b]) {
+                cout << "-1\n";
+                continue;
+            }
+
+            int g = group[choice];
+
+            cout << pos[a] + ((cyclepos[b] - cyclepos[choice]) % groupsize[g] + groupsize[g]) % groupsize[g] << '\n';
+            continue;
+        }
+
+        int diff = pos[a] - pos[b];
+
+        if (diff < 0) {
+            cout << "-1\n";
+            continue;
+        }
+
+        rep(i, 17) {
+            if ((diff >> i) & 1) {
+                a = lift[i][a];
+            }
+        }
+
+        if (a != b) {
+            cout << "-1\n";
+            continue;
+        }
+
+        cout << diff << '\n';
+    }
+}