/* -*- coding: utf-8 -*-
 *
 * 2999.cc:  No.2999 Long Long Friedrice - yukicoder
 */

#include<cstdio>
#include<vector>
#include<algorithm>

using namespace std;

/* constant */

const int MAX_N = 2000;
const int MAX_M = 1000000;

/* typedef */

using vi = vector<int>;

/* global variables */

int as[MAX_N], bs[MAX_N];
vi nbrs[MAX_M];
bool ds[MAX_M];

/* subroutines */

/* main */

int main() {
  int n;
  scanf("%d", &n);
  for (int i = 0; i < n; i++) scanf("%d", as + i), as[i]--;
  for (int i = 0; i < n; i++) scanf("%d", bs + i);

  int m = 0;
  for (int i = 0; i < n; i++) {
    nbrs[as[i]].push_back(as[i] + bs[i]);
    m = max(m, as[i] + bs[i]);
  }

  ds[0] = true;
  int maxu = 0;
  for (int u = 0; u <= m; u++)
    if (ds[u]) {
      maxu = u;
      for (auto v: nbrs[u]) ds[v] = true;
    }

  printf("%d\n", maxu + 1);
  
  return 0;
}