//转化为求逆序列

#include<cstdio>

typedef long long LL;
const int N=500010;

int n;
LL q[N],w[N];

LL merge_sort(int l,int r)
{
    if(l==r)return 0;

    int mid=l+r>>1;
    LL res=merge_sort(l,mid)+merge_sort(mid+1,r);
    int i=l,j=mid+1,k=0;
    while(i<=mid&&j<=r)
        if(q[i]<=q[j])w[k++]=q[i++];
        else
        {
            res+=mid-i+1;
            w[k++]=q[j++];
        }
    while(i<=mid)w[k++]=q[i++];
    while(j<=r)w[k++]=q[j++];

    for(int i=l,j=0;i<=r;i++,j++)q[i]=w[j];
    return res;
}


int main()
{
    while(scanf("%d",&n),n)
    {
        for(int i=0;i<n;i++)scanf("%d",&q[i]);
        printf("%lld\n",merge_sort(0,n-1));
    }
    return 0;
}