a = list(map(int, input().split()))
n = len(a)
count = 0
for i in range (n - 1):
    for j in range (n - i - 1):
        if a[j + 1] < a [j]:
            a[j], a[j + 1] = a[j + 1], a[j]
            count += 1
print(count)