N = int(input())
A = [0] + list(map(int,input().split()))
B = [0] + list(map(int,input().split()))
P = [0] * (N + 1)
Q = [0] * (N + 1)
for i in range(N + 1):
    P[A[i]] = i
for i in range(N + 1):
    Q[i] = P[B[i]]

from atcoder.fenwicktree import FenwickTree
ft = FenwickTree(N + 1)
cnt = 0
for x in Q:
    cnt += ft.sum(x, N + 1)
    ft.add(x, 1)
print(cnt)