#include "bits/stdc++.h"
using namespace std;

typedef long long Int;
#define REP(i,n) for(int (i)=0;(i)<(int)(n);++(i))

int A[1500];
int B[1500];
int main() {
	int N;
	cin >> N;
	REP(i, N) cin >> A[i];
	REP(i, N) cin >> B[i];

	int ans = 999999999;
	REP(i, N) {
		priority_queue<pair<int, int>> pq;
		REP(j, N) {
			pq.push(make_pair(-A[j], 0));
		}
		for (int j = 0; j < N; j++) {
			pair<int,int> top = pq.top();
			pq.pop();
			top.first -= B[(i + j) % N] / 2;
			top.second--;
			pq.push(top);
		}

		int maxButtle = 0;
		while (!pq.empty()) {
			int buttle = -pq.top().second;
			pq.pop();
			maxButtle = max(maxButtle, buttle);
		}
		ans = min(ans, maxButtle);
	}
	cout << ans << endl;
}