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

def count_inversion(sequence):
  return sum(sum(m<n for m in sequence[i+1:]) for i,n in enumerate(sequence))

print(count_inversion(C))