P1116 车厢重组

题目传送门

#include 

using namespace std;
const int N = 10010;
int a[N];
int n, cnt;

int main() {
    cin >> n;
    for (int i = 1; i <= n; i++) cin >> a[i];

    for (int i = 1; i < n; i++)
        for (int j = i + 1; j <= n; j++)
            if (a[i] > a[j]) {
                cnt++;
                swap(a[i], a[j]);
            }
    cout << cnt << endl;
    return 0;
}