def msort(l,r):
    if l >= r: return 0
    x = l+r>>1
    res = msort(l,x)+msort(x+1,r)
    i,j,temp = l,x+1,[]
    while i <= x and j <= r:
        if q[i] <= q[j]:
            temp.append(q[i])
            i+=1
        else:
            temp.append(q[j])
            j+=1
            res += x - i + 1
    while i <= x:
        temp.append(q[i])
        i+=1
    while j <= r:
        temp.append(q[j])
        j+=1
    i, j= l, 0
    while i <= r:
        q[i] = temp[j]
        i+=1
        j+=1

    return res

while True:
    q = []
    n = int(input())
    if n == 0 : break
    for i in range(n):
        q.append(int(input()))
    print(msort(0,n-1))