Kortit

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

void solve() {
	int n;
	cin >> n;

	int h = n/2;
	vector<int> vals(h);
	for (int i = 0; i < h; ++i) cin >> vals[i];
	sort(vals.begin(), vals.end());

	int res = 0, cur = 0, j = 1;
	for (auto i : vals) {
		while(i > j) {
			++j;
			++cur;
		}
		++j;
		if (cur > 0) {
			--cur;
			++res;
		}	
	}
	cout << res << '\n';
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(0);

	int t;
	cin >> t;
	for (int ti = 0; ti < t; ++ti) solve();
}

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 2

Verdict: ACCEPTED