Kortit

#include <bits/stdc++.h>
using namespace std;
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  int T;
  cin >> T;
  for (int Ti = 0; Ti < T; ++Ti) {
    int n;
    cin >> n;
    int z[n] {};
    deque<int> o, t;
    for (int i = 0; i < n/2; ++i) {
      int x;
      cin >> x;
      x--;
      z[x] = 1;
    }
    for (int i = 0; i < n; ++i) {
      if (z[i]) {
        o.push_back(i);
      } else {
        t.push_back(i);
      }
    }
    int res = 0;
    for (int i = 0; i < n/2; ++i) {
      if (o.back() > t.back()) {
        o.pop_back();
        res++;
      } else {
        o.pop_front();
      }
      t.pop_back();
    }
    cout << res << "\n";
  }
}

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 2

Verdict: ACCEPTED