#include <bits/stdc++.h> using namespace std; const int N = 5e4 + 10; int n, x, a[N]; long long ans = 0; int main(){ cin >> n; for ( int i = 1; i <= n; i++ ){ cin >> a[i]; } for ( int i = n; i > 1; i-- ){ bool ok = 1; for( int j = 1; j < i; j++ ){ if( a[j] > a[j + 1] ){ ans++; swap (a[j], a[j+1]); ok = 0; } } if ( ok ) { break; } } cout << ans; return 0; }