Sorting

#include <bits/stdc++.h>

#define int long long

using namespace std;

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int t;
    cin >> t;
    while (t--) {
        int n;
        cin >> n;
        int a[n];
        for (int i = 0; i < n; i++) cin >> a[i];
        int inv = 0;
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < i; j++) {
                if (a[i]<a[j]) inv++;
            }
        }
        if (n == 3) {
            if (inv == 0) cout << "YES\n";
            else cout << "NO\n";
            exit(0);
        }
        if (n == 4) {
            if (inv == 0 || (a[0] == 2 && a[1] == 1 && a[2] == 4 && a[3] == 3)) cout << "YES\n";
            else cout << "NO\n";
            exit(0);
        }
        if (inv%2==0) cout << "YES\n";
        else cout << "NO\n";
    }
}
/*

*/

Test 1

Group: 1, 2

Verdict: WRONG ANSWER

Test 2

Group: 2

Verdict: WRONG ANSWER

Test 3

Group: 1, 2

Verdict: ACCEPTED

Test 4

Group: 1, 2

Verdict: ACCEPTED