import sys
sys.setrecursionlimit(10 ** 8)
from collections import defaultdict
n=int(input())
A=list(map(int,input().split()))
B=list(map(int,input().split()))
D=defaultdict(list)
F=defaultdict(int)
for i,j in zip(A,B):
    D[i].append(i+j)
ans=1
def dfs(x):
    global ans
    F[x]=1
    ans=max(ans,x)
    for i in D[x]:
        if F[i]==0:
            dfs(i)
dfs(1)
print(ans)