using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;
class Program
{
    static int NN => int.Parse(ReadLine());
    static long[] NList => ReadLine().Split().Select(long.Parse).ToArray();
    public static void Main()
    {
        var c = NList;
        var ans = c[0] + c[1];
        for (var i = 1; i <= Math.Min(c[0], c[1]); ++i)
        {
            ans = Math.Min(ans, Math.Abs(c[0] + c[1] - 4 * i));
        }
        WriteLine(ans);
    }
}