using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Text;
using System.Text.RegularExpressions;
using System.Linq;
using System.IO;

class Program
{
    static void Main(string[] args)
    {
        Magatro m = new Magatro();
        m.Scan();
        m.Solve();
    }
}

public class Scanner
{
    private StreamReader Sr;
    private string[] S;
    private int Index;
    private const char Separator = ' ';
    public Scanner()
    {
        Index = 0;
        S = new string[0];
        Sr = new StreamReader(Console.OpenStandardInput());
    }
    private string[] Line()
    {
        return Sr.ReadLine().Split(Separator);
    }
    public string Next()
    {
        string result;
        if (Index >= S.Length)
        {
            S = Line();
            Index = 0;
        }
        result = S[Index];
        Index++;
        return result;
    }
    public int NextInt()
    {
        return int.Parse(Next());
    }
    public double NextDouble()
    {
        return double.Parse(Next());
    }
    public long NextLong()
    {
        return long.Parse(Next());
    }
    public string[] StringArray(int index = 0)
    {
        Next();
        Index = S.Length;
        return S.Skip(index).ToArray();
    }
    public int[] IntArray(int index = 0)
    {
        return StringArray(index).Select(int.Parse).ToArray();
    }
    public long[] LongArray(int index = 0)
    {
        return StringArray(index).Select(long.Parse).ToArray();
    }
    public bool ScanToEnd(ref string s)
    {
        if (Sr.EndOfStream)
        {
            return false;
        }
        else
        {
            s = Sr.ReadLine();
            return true;
        }
    }
}

public class Magatro
{
    private PriortyQueue<Monstar> Q;
    private int N;
    private int[] B;
    private int ans = int.MaxValue;
    public void Scan()
    {
        Scanner sc = new Scanner();
        N = sc.NextInt();
        B = new int[N];
        Init();
        for (int i = 0; i < N; i++)
        {
            Q.Push(new Monstar(sc.NextInt()));
        }
        for (int i = 0; i < N; i++)
        {
            B[i] = sc.NextInt();
        }
    }
    private void Init()
    {
        Q = new PriortyQueue<Monstar>(Compare);
    }
    public void Solve()
    {
        for (int i = 0; i < N; i++)
        {
            ans = Math.Min(ans, Cnt(i));
        }
        Console.WriteLine(ans);
    }

    private int Cnt(int first)
    {
        if (first < 0 || N <= first)
        {
            throw new IndexOutOfRangeException();
        }
        PriortyQueue<Monstar> cp = Q.Clone();
        for (int i = 0; i < N; i++)
        {
            Monstar mon = cp.Pop();
            mon.Battle++;
            if (ans <= mon.Battle)
            {
                return int.MaxValue;
            }
            mon.Level += B[(first + i) % N] / 2;
            cp.Push(mon);
        }
        int max = -1;
        Monstar[] arr = cp.ToArray();
        for (int i = 0; i < N; i++)
        {
            max = Math.Max(max, arr[i].Battle);
        }
        return max;
    }
    private int Compare(Monstar a, Monstar b)
    {
        if (a.Level != b.Level)
        {
            return a.Level.CompareTo(b.Level);
        }
        else
        {
            return a.Battle.CompareTo(b.Battle);
        }
    }
}

public struct Monstar
{
    public int Battle;
    public int Level;
    public Monstar(int lebel)
    {
        Level = lebel;
        Battle = 0;
    }
}

public class PriortyQueue<T>
{
    private Comparison<T> Compare;
    private List<T> L;
    public PriortyQueue(Comparison<T> compare)
    {
        Compare = compare;
        L = new List<T>();
    }
    public PriortyQueue(Comparison<T> compare, List<T> list) : this(compare)
    {
        L = list.ToList();
    }
    public void Push(T item)
    {
        if (L.Count == 0)
        {
            L.Add(item);
            return;
        }
        if (Compare(L[0], item) > 0)
        {
            L.Insert(0, item);
            return;
        }
        if (Compare(item, L.Last()) > 0)
        {
            L.Add(item);
            return;
        }

        int left = 0;
        int right = L.Count - 1;
        while (left != right)
        {
            int index = (left + right) / 2;
            switch (Compare(L[index], item))
            {
                case 1:
                    right = index;
                    break;
                case -1:
                    left = index + 1;
                    break;
                case 0:
                    L.Insert(index, item);
                    return;
                default:
                    throw new Exception();
            }
        }
        L.Insert(right, item);
    }
    public T Peak()
    {
        if (L.Count < 1)
        {
            throw new IndexOutOfRangeException();
        }
        return L[0];
    }
    public T Pop()
    {
        T ret = Peak();
        L.RemoveAt(0);
        return ret;
    }
    public T[] ToArray()
    {
        return L.ToArray();
    }
    public PriortyQueue<T> Clone()
    {
        return new PriortyQueue<T>(Compare, L);
    }
}