#include"bits/stdc++.h"
//#include<bits/stdc++.h>
using namespace std;
#define print(x) cout<<x<<endl;
#define rep(i,a,b) for(int i=a;i<b;i++)
typedef long long ll;
const ll mod = 200000;

int main() {
	int n;
	int a[1502], b[1502];
	cin >> n;
	rep(i, 0, n) { cin >> a[i] ; }
	rep(i, 0, n) { cin >> b[i]; }
	int ans = n;
	rep(i, 0, n) {
		priority_queue<pair<int, int>> pq;
		for (int j = 0; j < n; j++) { pq.push(make_pair(-a[j], 0)); }
		rep(j, 0, n) {
			int up = b[(i + j) % n]/2;
			auto now = pq.top();
			pq.pop();
			pq.push(make_pair(now.first - up, now.second - 1));
		}

		int temp = 0;
		while (!pq.empty()) {
			auto now = pq.top(); pq.pop();
			temp = max(-now.second, temp);
		}
		ans = min(temp, ans);
	}
	print(ans);
}