import sys
input = sys.stdin.readline

class SCC:
	def __init__(self, n):
		self.n = n
		self.route = [[] for _ in [0] * n]
		self.rev_route = [[] for _ in [0] * n]
		self.label = [-1] * n
		self.count = 0
	
	def add_edge(self, v_first, v_second):
		self.route[v_first].append(v_second)
		self.rev_route[v_second].append(v_first)

	def _build(self):
		self.v_list = []
		self.visited = set([])
		for v in range(self.n):
			if(v in self.visited):
				continue
			self._dfs(v)
		for v in reversed(self.v_list):
			if(self.label[v] != -1):
				continue
			self._rev_dfs(v)
			self.count += 1

	def _dfs(self, v_start):
		stack = [v_start, 0]
		while(stack):
			v, id = stack[-2:]
			if(id == 0 and v in self.visited):
				stack.pop()
				stack.pop()
				continue
			self.visited.add(v)
			if(id < len(self.route[v])):
				stack[-1] += 1
				stack.extend([self.route[v][id], 0])
				continue
			stack.pop()
			self.v_list.append(stack.pop())

	def _rev_dfs(self, v_start):
		stack = [v_start]
		self.label[v_start] = self.count
		while(stack):
			v_now = stack.pop()
			for v_next in self.rev_route[v_now]:
				if(self.label[v_next] != -1):
					continue
				self.label[v_next] = self.count
				stack.append(v_next)

	def construct(self):
		self._build()
		dag = [[] for _ in [0] * self.count]
		group = [[] for _ in [0] * self.count]
		for v, lb in enumerate(self.label):
			for v_next in self.route[v]:
				lb_next = self.label[v_next]
				if(lb == lb_next):
					continue
				dag[lb].append(lb_next)
			group[lb].append(v)
		return dag, group



"""
Main Code
"""

N = int(input())
A = list(map(int, input().split()))
B = list(map(int, input().split()))
c = list(map(int, input().split()))

scc = SCC(N)
for i, k in enumerate(c):
	if(i == k - 1):
		continue
	scc.add_edge(k - 1, i)
dag, groups = scc.construct()

n = len(groups)
a = [0] * n
b = [0] * n
for i, g in enumerate(groups):
	a[i] = sum(A[k] for k in g)
	b[i] = sum(B[k] for k in g)

rdag = [[] for _ in [0] * n]
for i, lis in enumerate(dag):
	for v in lis:
		rdag[v].append(i)

def check(mid):
	visited = set([])
	dp = [aa - mid * bb for aa, bb in zip(a, b)]
	for x in range(n - 1, -1, -1):
		if(x in visited):
			continue
		visited.add(x)
		if(dp[x] > 0):
			dp[x] = 0
		if(not(rdag[x]) and dp[x] < 0):
			return False
		for y in rdag[x]:
			dp[y] += dp[x]
	return True

ok = 0
ng = sum(a) // sum(b) + 1
while(ng - ok > 1):
	mid = (ok + ng) >> 1
	if(check(mid)):
		ok = mid
	else:
		ng = mid
print(ok)