#include<iostream>
#include<fstream>
#include<sstream>
#include<string>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<ctime>
#include<stack>
#include<queue>
#include<set>
#include<map>
#include<vector>
#include<list>
#include<algorithm>
#include<utility>
#include<complex>
#include<functional>
using namespace std;

int a[1500], b[1500];
typedef pair<int, int> P;
const int inf = 1e9;
int main(void){
	int N;
	cin >> N;
	for (int i = 0; i < N; i++)
	{
		cin >> a[i];
	}
	for (int i = 0; i < N; i++)
	{
		cin >> b[i];
		b[i] >>= 1;
	}

	int res = inf;
	for (int i = 0; i < N; i++)
	{
		int maxim = 0;
		priority_queue< P ,vector<P>,greater<P>> que;
		for (int j = 0; j < N; j++)
		{
			que.push(make_pair(a[j], 0));
		}
		for (int j = 0; j < N; j++){
			int now = i + j;
			now = (now < N) ? now : now - N;
			auto p = que.top(); que.pop();
			//printf("(%d,%d)-%d\n", p.first, p.second,b[now]);
			p.first += b[now];
			p.second++;
			maxim = max(maxim, p.second);
			
			que.push(p);
		}
		res = min(res, maxim);
		
	}
	cout << res << endl;

	return 0;
}