N = int(input())
A = {int(x):i for i,x in enumerate(input().split())}
B = list(map(int, input().split()))

exch = 0
for i in range(len(B)-1, 0, -1):
    for j in range(i):
        if A[B[j]] > A[B[j+1]]:
            B[j], B[j+1] = B[j+1], B[j]
            exch += 1
print(exch)