Add a bunch of other problems.

Some are not finished...

Codeforces Round 1020 (Div. 3)/D. Flower Boy.cpp

@@ -0,0 +1,136 @@
+/* Problem URL: https://codeforces.com/contest/2106/problem/D */
+
+#include <bits/stdc++.h>
+
+using namespace std;
+
+#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 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, m;
+        cin >> n >> m;
+
+        vl a(n);
+        cin >> a;
+        vl b(m);
+        cin >> b;
+        b.push_back(0);
+
+        vi pref(m, -1);
+        vi suf(m, -1);
+
+        int now = 0;
+        for (int i = 0; i < n && now < m; i++) {
+            if (a[i] >= b[now]) {
+                pref[now] = i;
+                now++;
+            }
+        }
+
+        now = m - 1;
+        for (int i = n - 1; i >= 0 && now >= 0; i--) {
+            if (a[i] >= b[now]) {
+                suf[now] = i;
+                now--;
+            }
+        }
+
+        ll ans = INT64_MAX >> 1;
+
+        if (pref.back() != -1) {
+            cout << "0\n";
+            continue;
+        }
+
+        if (m == 1) {
+            cout << b[0] << '\n';
+            continue;
+        }
+
+        if (pref[m - 1] == -1 && pref[m - 2] != -1) {
+            rmin(ans, b[m - 1]);
+        }
+        
+        if (suf[1] != -1 && suf[0] == -1) {
+            rmin(ans, b[0]);
+        }
+
+        for (int i = 1; i < m - 1; i++) {
+            if (pref[i - 1] != -1 && suf[i + 1] != -1 && pref[i - 1] < suf[i + 1]) {
+                rmin(ans, b[i]);
+            }
+        }
+
+        cout << (ans == INT64_MAX >> 1 ? -1 : ans) << '\n';
+    }
+}