class BIT():#1-indexed
	def __init__(self, size):
		self.table = [0 for _ in range(size+2)]
		self.size = size

	def Sum(self, i):#1からiまでの和
		s = 0
		while i > 0:
			s += self.table[i]
			i -= (i & -i)
		return s

	def PointAdd(self, i, x):#
		while i <= self.size:
			self.table[i] += x
			i += (i & -i)
		return

n = int(input())
a = list(map(int, input().split()))
p = [-1 for _ in range(n+1)]
for i, x in enumerate(a):
	p[x] = i+1
b = list(map(int, input().split()))
q = [p[x] for x in b]
ans = 0
bit = BIT(n+1)
for x in q[::-1]:
	ans += bit.Sum(x)
	bit.PointAdd(x, 1)
print(ans)