#include <cstdio>
#include <queue>
using namespace std;

#define N_MAX 1500

struct State {
	int level, turn;
	State(int l) : level(l), turn(0) {}
	bool operator < (const State& r) const {
		if (level != r.level) return level > r.level;
		return turn > r.turn;
	}
};

int N;
int A[N_MAX], B[N_MAX];

int main() {
	scanf("%d", &N);
	for (int i = 0; i < N; i++) scanf("%d", A + i);
	for (int i = 0; i < N; i++) scanf("%d", B + i);
	
	int res = N_MAX + 1;
	
	priority_queue<State> pq;
	for (int i = 0; i < N; i++) {
		for (int j = 0; j < N; j++) pq.emplace(A[j]);
		int j = i, cnt = 0;
		while (cnt != N) {
			State s = pq.top();
			pq.pop();
			s.level += B[j] / 2;
			s.turn++;
			pq.push(s);
			j = (j + 1) % N;
			cnt++;
		}
		int maxi = 0;
		while (pq.size()) {
			maxi = max(maxi, pq.top().turn);
			pq.pop();
		}
		res = min(res, maxi);
	}
	
	printf("%d\n", res);
	
	return 0;
}