#include <bits/stdc++.h>
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define chmax(a, b) a = max(a, b)
#define chmin(a, b) a = min(a, b)
#define all(x) (x).begin(), (x).end()
using namespace std;
using ll = long long;
using P = pair<int,int>;
using VI = vector<int>;
using VVI = vector<VI>;

int main() {
    int n;
    cin >> n;
    VI a(n), b(n);
    rep(i, n) cin >> a[i];
    rep(i, n) cin >> b[i];
    int ans = n;
    rep(s, n) {
        priority_queue<P,vector<P>,greater<P>> q;
        rep(i, n) q.emplace(a[i],0);
        int mx = 0;
        rep(j, n) {
            int ai, ci;
            tie(ai, ci) = q.top(); q.pop();
            q.emplace(ai + b[(s+j)%n] / 2, ci + 1);
            chmax(mx, ci + 1);
        }
        chmin(ans, mx);
    }
    cout << ans << endl;
}