洛谷P1116 车厢重组进阶解法

#include<iostream>

using namespace std;
int N, a[10000], s;

int main()
{
	cin >> N;
	for (int i = 0; i < N; i++)
		cin >> a[i];
	for (int i = 0; i < N; i++)
		for (int j = i + 1; j < N; j++)
			if (a[i] > a[j])
				s++;
	cout << s;
	return 0;
}