#include<iostream>
using namespace std;
int A[10000];
int main()
{
	int n,sum=0;
	cin >> n;
	for (int i = 0; i < n; i++)cin >> A[i];

	for(int i=0;i<n-1;i++)
		for (int j = 1; j < n - i; j++)
		{
			if (A[j-1] > A[j])
			{
				int t = A[j];
				A[j] = A[j-1];
				A[j-1] = t;
				sum++;
			}
		}
	cout << sum;

}