// 107
#include <bits/stdc++.h>
using namespace std;
int n;
int a[500005], tmp[500005];
long long ms(int l, int r)
{
    if (l == r)
        return 0;
    int mid = l + r >> 1;
    long long ans = 0;
    ans = ms(l, mid) + ms(mid + 1, r);
    int i = l, j = mid + 1, tot = l;
    while (i <= mid && j <= r)
    {
        if (a[i] > a[j])
            tmp[tot++] = a[j++], ans+=j-tot;
        else
            tmp[tot++] = a[i++];
    }
    while (i <= mid)
        tmp[tot++] = a[i++];
    while (j <= r)
        tmp[tot++] = a[j++];
    for (int i = l; i <= r; ++i)
        a[i] = tmp[i];
    return ans;
}
int main()
{
    scanf("%d", &n);
    while (n != 0)
    {
        for (int i = 1; i <= n; ++i)
            scanf("%d", &a[i]);
        printf("%lld\n", ms(1, n));
        scanf("%d", &n);
    }
    return 0;
}