#include <iostream>
#include <string>
#include <utility>
#include <algorithm>
#include <map>
#include <set>
#include <vector>
#include <cmath>
#include <cstdlib>
#include <queue>
#include <stack>
#include <iomanip>

using namespace std;

#define REP(i, n) for(ll i = 0;i < n;i++)
#define REPR(i, n) for(ll i = n;i >= 0;i--)
#define FOR(i, m, n) for(ll i = m;i < n;i++)
#define FORR(i, m, n) for(ll i = m;i >= n;i--)
#define REPO(i, n) for(ll i = 1;i <= n;i++)
#define ll long long
#define INF (ll)1 << 60
#define MINF (-1 * INF)
#define ALL(n) n.begin(),n.end()
#define MOD 1000000007
#define P pair<ll, ll>

ll n, ans = INF;
int main() {
	cin >> n;
	vector<ll>a(n), b(n);
	REP(i, n)cin >> a[i];
	REP(i, n)cin >> b[i];
	REP(i, n)b.push_back(b[i]);
	REP(i, n) {
		ll nowans = 0;
		priority_queue<P, vector<P>, greater<P> > q;
		REP(i, n)q.push(P(a[i], 0));
		FOR(j, i, i + n) {
			P now = q.top();
			q.pop();
			now.first += b[j] / 2;
			now.second++;
			q.push(now);
		}
		while (!q.empty()) {
			nowans = max(nowans, q.top().second);
			q.pop();
		}
		ans = min(ans, nowans);
	}
	cout << ans << endl;
}