#include <cstdio>

const int MAXN = 1000;
int array[MAXN];

int main() {
    int N;
    scanf("%d", &N);
    for (int i = 0; i < N; ++i) {
        scanf("%d", &array[i]);
    }
    int P = 0;
    for (int i = 0; i < N; ++i) {
        for (int j = 0; j + 1 < N; ++j) {
            if (array[j] > array[j + 1]) {
                int z = array[j];
                array[j] = array[j + 1];
                array[j + 1] = z;
                ++P;
            }
        }
    }
    printf("%d\n", P);
    return 0;
}