#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <climits>
#include <cfloat>
#include <map>
#include <utility>
#include <set>
#include <iostream>
#include <memory>
#include <string>
#include <vector>
#include <algorithm>
#include <functional>
#include <sstream>
#include <complex>
#include <stack>
#include <queue>
#include <cstring>

using namespace std;

int main(){
  int N;
  cin >> N;
  int A[N];
  int B[N];
  for( int i = 0 ; i <N; i++ ) cin >> A[i];
  for( int i = 0 ; i <N; i++ ) cin >> B[i];
  int ans = INT_MAX;
  for( int i = 0 ; i <N; i++ ){
    int curAns = 0;
    priority_queue<pair<int,int> > q;
    for( int j = 0 ; j <N ; j++){
      q.push(make_pair(-A[j],0));
    }
    for( int j = 0 ; j <N; j++ ){
      int ind = (i+j)%N;
      pair<int,int> p = q.top();
      q.pop();
      q.push( make_pair(p.first-B[ind]/2,p.second+1));
      curAns = max(curAns,p.second+1);
    }
    ans = min(ans,curAns);
  }
  cout << ans << endl;

  return 0;
}