#include <bits/stdc++.h>
using namespace std;
using ll=long long;
vector<ll> g[100001]; 
vector<ll> c(100001);
pair<ll, ll> megero[100001];
vector<ll> penz(100001);
ll dfs(int x){
	if (c[x]==0){
		return (penz[x]);
	}
	else{
		ll ans=0; 
		for (int edge:g[x]){
			ans+=dfs(edge);
		}
		megero[x]={penz[x],ans};
	}
	return (max(megero[x].first, megero[x].second));
}
int main() {
	int n;
	cin>>n;
	for (int i=1; i<=n;i++){
		cin>>penz[i];
	}
	for (int i=2; i<=n;i++){
		ll x;
		cin>>x;
		c[x]++; 
		g[x].push_back(i);
	}
	dfs(1);
	cout<<max(megero[1].first, megero[1].second); 
}