#include<iostream>
#include<cstring>
#include<algorithm>
using namespace std;
const int maxn = 5e5+10;
int c[maxn],ord[maxn];
struct Node{
int val;
int id;
}node[maxn];
int cmp(Node a,Node b)
{
    return a.val<b.val;
}
int lowbit(int x)
{
    return x&(-x);
}
void update(int x)
{
    while(x<=maxn-9)
    {
        c[x]+=1;
        x+=lowbit(x);
    }
}
int sum(int x)
{
    int sum1=0;
    while(x>0)
    {
        sum1+=c[x];
        x-=lowbit(x);
    }
    return sum1;
}
int main()
{
    int n;
    while(~scanf("%d",&n)&&n)
    {
        memset(c,0,sizeof(c));
        for(int i=1;i<=n;i++)
            {
                scanf("%d",&node[i].val);
                node[i].id=i;
            }
        sort(node+1,node+n+1,cmp);
        for(int i=1;i<=n;i++)
            ord[i]=node[i].id;
        long long  sum1=0;
        for(int i=1;i<=n;i++)
        {
            update(ord[i]);
            sum1+=i-sum(ord[i]);
        }
        cout << sum1 << endl;
    }
    return 0;
}