#include <iostream>
using namespace std;

int main() {
int n;

while ( cin >> n ) {
int train[n], cnt = 0;

for ( int i = 0; i < n; ++i )
cin >> train[i];

for ( int i = 0; i < n - 1; ++i )
for ( int j = 0; j < n - i - 1; ++j )
if ( train[j] > train[j + 1] ) {
train[j] ^= train[j + 1] ^= train[j] ^= train[j + 1];
++cnt;
}

cout << cnt << endl;
}

return 0;
}