using System;
using System.Linq;
using System.Collections.Generic;
using System.Text;

public class Program
{
    public void Proc() {
        Reader.IsDebug = false;
        int itemCount = int.Parse(Reader.ReadLine());
        long[] items = Reader.ReadLine().Split(' ').Select(a=>long.Parse(a)).OrderByDescending(a=>a).ToArray();
        long range = Reader.ReadLine().Split(' ').Select(a=>Math.Abs(long.Parse(a))).Max();

        long ans = 0;
        ans += (range / (items[0]*2));
        long amari = range % (items[0]*2);
        if(amari == 0) {

        }else if(amari == items[0]) {
            amari++;
        } else {
            amari+=2;
        }
        Console.WriteLine(amari);
    }


    public class Reader {
        public static bool IsDebug = true;
        private static System.IO.StringReader SReader;
        private static string InitText = @"


3
3 4 5
12 12



";
        public static string ReadLine() {
            if(IsDebug) {
                if(SReader == null) {
                    SReader = new System.IO.StringReader(InitText.Trim());
                }
                return SReader.ReadLine();
            } else {
                return Console.ReadLine();
            }
        }
    }
    public static void Main(string[] args)
    {
        Program prg = new Program();
        prg.Proc();
    }
}