#include <stdio.h>
#include <stdlib.h>

int main(int argc, char const *argv[])
{
    int A[10000]={0};
	int N,k;
	k=0;
	scanf("%d",&N);
	while(N!=0){
		scanf("%d",&A[k]);
		k++;
		N--;
	}
	int count = 0 ;
	int temp;
	for (int i = k-1; i >= 0; --i)
	{
		for (int j = 0; j < i; ++j)
		{
			if (A[j]>A[j+1])
			{
				temp = A[j];
				A[j]=A[j+1];
				A[j+1]=temp;
				count++;
			}
		}
	}
	printf("%d",count);
	return 0;
}