#include <iostream>
#include <vector>
#include <queue>
#include <string>
#include <cstring>
#include <cstdio>
#include <sstream>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <set>
#include <map>
#include <list>
#include <iomanip>

#define INF 1000000001
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define RFOR(i, a, b) for (int i = (a); i >= (b); i--)

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
const double PI = acos(-1.0);

int N;
int A[1501], B[1501];

int main()
{
	ios::sync_with_stdio(false);

	cin >> N;
	FOR(i,0,N) cin >> A[i];
	FOR(i,0,N) cin >> B[i];

	FOR(i,0,N) B[i] /= 2;

	int ans=INF;
	FOR(st,0,N) {
		priority_queue< pair<int, int> > heap;
		FOR(i,0,N) heap.push(pii (-A[i], 0));
		FOR(i,0,N) {
			int e = (st+i) % N;
			pii p = heap.top(); heap.pop();
			heap.push(pii(p.first-B[i], p.second-1));
		}
		int t = 0;
		while (!heap.empty()) {
			pii p = heap.top(); heap.pop();
			t = max(t, -p.second);
		}
		ans = min(ans, t);
	}
	cout << ans << endl;
	return 0;
}