#include <bits/stdc++.h>
using namespace std;
template<class T> using pq = priority_queue<T>;
template<class T> using pqg = priority_queue<T, vector<T>, greater<T>>;

int main(){
    int N;
    cin >> N;
    vector<int> A(N), B(N);
    for (int& x : A) cin >> x;
    for (int& x : B) cin >> x;

    int ans = N;
    for (int i = 0; i < N; i++){
        pqg<pair<int, int>> Q;
        for (int x : A) Q.emplace(x, 0);
        for (int j = 0; j < N; j++){
            auto [a, b] = Q.top();
            Q.pop();
            int c = B[(i+j)%N];
            a += c/2, b++;
            Q.emplace(a, b);
        }
        int mx = 0;
        while (!Q.empty()){
            mx = max(mx, Q.top().second);
            Q.pop();
        }
        ans = min(ans, mx);
    }

    cout << ans << endl;
}