import typing

class FenwickTree:
    '''Reference: https://en.wikipedia.org/wiki/Fenwick_tree'''

    def __init__(self, n: int = 0) -> None:
        self._n = n
        self.data = [0] * n

    def add(self, p: int, x: typing.Any) -> None:
        assert 0 <= p < self._n

        p += 1
        while p <= self._n:
            self.data[p - 1] += x
            p += p & -p

    def sum(self, left: int, right: int) -> typing.Any:
        assert 0 <= left <= right <= self._n

        return self._sum(right) - self._sum(left)

    def _sum(self, r: int) -> typing.Any:
        s = 0
        while r > 0:
            s += self.data[r - 1]
            r -= r & -r

        return s


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]]

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