#include
     
      long long cnt;long long  a[500001],t[500001];void merge(long long *a,long long *t,int l,int m,int r){    int p = l;    int q = m+1;    int k = p;    while(p <= m||q <= r)    {        if(q > r||(p <= m&&a[p] <= a[q]))            t[k++] = a[p++];        else        {            cnt += m-p+1;            t[k++]=a[q++];        }    }    for(int i = l; i <= r; i++)a[i]=t[i];}void mergesort(long long *a,long long *t,int l,int r){    if(r > l)    {        int m = (l+r)/2;        mergesort(a,t,l,m);        mergesort(a,t,m+1,r);        merge(a,t,l,m,r);    }}int main(){    int n;    while(~scanf("%d", &n))    {        if(n==0)            break;        cnt = 0;        for(int i = 0; i < n; i++)            scanf("%lld", &a[i]);        mergesort(a,t,0,n-1);        printf("%lld\n", cnt);    }    return 0;}