#include <iostream>
#include <vector>
#include <cmath>
#include <map>
#include <set>
#include <iomanip>
#include <queue>
#include <algorithm>
#include <numeric>
#include <deque>
#include <complex>

using namespace std;

template<typename T> using pq = priority_queue<T, vector<T>, greater<T>>;

int main(){

    long long N, A, level, cnt, mx, ans=1e18;
    cin >> N;
    pq<pair<long long, long long>> que1, que2;
    vector<long long> B(N);
    for (int i=0; i<N; i++){
        cin >> A;
        que1.push({A, 0});
    }

    for (int i=0; i<N; i++) cin >> B[i];

    for (int i=0; i<N; i++){
        que2 = que1;
        mx = 0;
        for (int j=i; j<N; j++){
            tie(level, cnt) = que2.top(); que2.pop();
            cnt++;
            level += B[j]/2;
            que2.push({level, cnt});
            mx = max(mx, cnt);
        }
        for (int j=0; j<i; j++){
            tie(level, cnt) = que2.top(); que2.pop();
            cnt++;
            level += B[j]/2;
            que2.push({level, cnt});
            mx = max(mx, cnt);
        }
        ans = min(ans, mx);
    }

    cout << ans << endl;

    return 0;
}