#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using ll = long long;
using mint = atcoder::modint998244353;
using maxt = atcoder::modint1000000007;

int ans = 0;
vector<vector<int>> To(1000001, vector<int>(0, 0));
vector<bool> seen(1000001, false);
void dfs(int v) {
	ans = max(ans, v);
	seen.at(v) = true;
	for(int next_v : To.at(v)) {
		if(seen.at(next_v)) {
			continue;
		}
		dfs(next_v);
	}
}

int main() {
	int N;
	cin >> N;
	vector<int> A(N);
	for(int &o : A) {
		cin >> o;
	}
	vector<int> B(N);
	for(int &o : B) {
		cin >> o;
	}
	assert(N <= 2000);
	for(int i = 0; i < N; i++) {
		assert(A.at(i) <= 500000);
		assert(B.at(i) <= 500000);
	}
	for(int i = 0; i < N; i++) {
		To.at(A.at(i)).push_back(A.at(i) + B.at(i));
	}
	dfs(1);
	cout << ans << endl;
}