#include <iostream>
using namespace std;
int n;

int main() {
    cin >> n;
    int arr[n];

    for(int i=0; i<n; i++) cin >> arr[i];
    int counter=0;
   for(int u=0; u<n;u++) {
        for(int j=1; j<(n-u); j++) {
            if((arr[j]<arr[j-1])) {
            	
                int prev;
                prev = arr[j-1];
                arr[j-1] = arr[j];
                arr[j] = prev;
                counter++;
                	//for(int t=0; t<n; t++) cout << arr[t] << " ";
                	//cout << "   " << u;
                	//cout<<'\n';
            }
        }
    }
    cout << counter;
    return 0;
}