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

using namespace std;
typedef pair<int, int> pii;

int main() {	
	int n;
	cin >> n;

	int level_allys[1500];
	int level_enemys[1500];
	
	for (int i = 0; i < n; i++) {
		cin >> level_allys[i];
	}

	for (int i = 0; i < n; i++) {
		cin >> level_enemys[i];
	}

	priority_queue<pii, vector<pii>, greater<pii>> q;
	int ans = numeric_limits<int>::max();
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < n; j++) {
			q.push(make_pair(level_allys[j], 0));
		}
		for (int j = 0; j < n; j++) {
			auto pair = q.top();
			q.pop();
			int add = level_enemys[(i + j) % n] / 2;
			q.push(make_pair(pair.first + add, pair.second + 1));
		}

		int max_count = 0;
		while (q.size() > 0) {
			auto pair = q.top();
			q.pop();
			max_count = max(max_count, pair.second);
		}

		ans = min(ans, max_count);
	}

	cout << ans << endl;

	return 0;
}