n = int(input())
a = list(map(int,input().split()))
b = list(map(int,input().split()))
D = {v:i for i,v in enumerate(b)}
bit = [0] * (n+1)
def update(i,x):
    while i <= n:
        bit[i] += x
        i += i & -i
def fold(i):
    ans = 0
    while i > 0:
        ans += bit[i]
        i -= i & -i
    return ans
ans = 0
for x in reversed(a):
    ans += fold(D[x]+1)
    update(D[x]+1,1)
print(ans)