#include <iostream>
#include <queue>
#include <functional>
#include <algorithm>

typedef std::pair<int, int> P; //Lv,cnt
typedef std::priority_queue< P, std::vector<P>, std::greater<P> > Q;

int n;
int a[1501], b[1501];
int ans = 100000000;

int main(){
	std::cin >> n;
	for (int i = 0; i < n; i++)std::cin >> a[i];
	for (int i = 0; i < n; i++)std::cin >> b[i];

	for (int i = 0; i < n; i++){
		Q que;
		for (int j = 0; j < n; j++)que.push(P(a[j], 0));

		for (int j = 0; j < n; j++){
			int t = (i + j) % n;

			P p = que.top();
			que.pop();

			p.first += b[t] / 2;
			p.second++;

			que.push(p);
		}

		int max = 0;
		for (int i = 0; i < n; i++){
			P p = que.top();
			que.pop();
			max = std::max(max, p.second);
		}

		ans = std::min(ans, max);
	}

	std::cout << ans << std::endl;

	return 0;
}