//#include <algorithm>
//#include <cmath>
//#include <cstring>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <set>
//#include <sstream>
//#include <stack>
#include <string>
#include <vector>
#include <iterator>

//#define pb push_back
//#define puts(x) cout << #x << " : " << x << endl;
//#pragma GCC diagnostic ignored "-Wconversion"
//#define REP(i,n) for (int i=0;i<(n);i++)
//#define REPE(i,n) for (int i=0;i<=(n);i++)
//#define init(a,b) memset((a), (b), (sizeof(a)));
//#define PI 3.14159265
//#define EPS (1e-10)
//#define EQ(a,b) (abs((a)-(b)) < EPS)

using namespace std;

//typedef long long ll;

#define int long long

typedef pair<int, int> P;

int a[1600],b[1600];

map<int, priority_queue<int, vector<int>, greater<int> > > level_times;

signed main() {
    std::ios::sync_with_stdio(false);

    int n;
    cin >> n;
    for(int i=0;i<n;i++){
//        cout << i << endl;
        cin >> a[i];
    }
    for(int i=0;i<n;i++){
//        cout << i << endl;
        cin >> b[i];
    }

    map<int, priority_queue<int, vector<int>, greater<int> > > level_times;
    for(int i=0;i<n;i++){
//        cout<<i<<endl;
        level_times[a[i]].push(0);
    }


    int res = 1000*1000*1000;;
    for(int i=0;i<n;i++){
        int mx = 0;
//        cout<<n<<':'<<i<<endl;
        map<int, priority_queue<int, vector<int>, greater<int> > > level_times;
        for(int j=0;j<n;j++){
            level_times[a[j]].push(0);
        }
        for(int j=0;j<n;j++){
            int idx = (i+j) % n;

            int level = level_times.begin()->first;

            int times = level_times[level].top();
            level_times[level].pop();
            if(level_times[level].empty()){
                level_times.erase(level);
            }
//            cout<<"********************"<<endl;
//            cout<<b[idx]<<':'<<level<<':'<<times<<endl;
            level += b[idx]/2;
            times += 1;
//            cout<<b[idx]<<':'<<level<<':'<<times<<endl;
//            cout<<"********************"<<endl;
            level_times[level].push(times);
            mx = max(mx, times);
        }
        res = min(mx, res);
    }

    cout<<res<<endl;

    return 0;
}