#include <stdio.h>#include <stdlib.h>int Data[ 500005 ];int Save[ 500005 ];long long MergeSort( int a, int b ){ if ( a < b ) { long long L = MergeSort( a, (a+b)/2 ); long long R = MergeSort( (a+b)/2+1, b ); long long Count = L+R; int ps = a,pe = (a+b)/2; int qs = (a+b)/2+1,qe = b; int move = a; while ( ps <= pe || qs <= qe ) if ( qs <= qe && ( ps == pe+1 || Data[ ps ] > Data[ qs ] ) ) { Save[ move ++ ] = Data[ qs ++ ]; Count += pe-ps+1LL; }else Save[ move ++ ] = Data[ ps ++ ]; for ( int i = a ; i <= b ; ++ i ) Data[ i ] = Save[ i ]; return Count; }else return 0LL;} int main(){ int n; while ( scanf("%d",&n) && n ) { for ( int i = 1 ; i <= n ; ++ i ) scanf("%d",&Data[ i ]); printf("%lldn",MergeSort( 1, n )); } return 0;}
