BitFlipper

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

namespace BitFlipper
{
    class BitFlipper
    {
        public static string ConvertToBinary(ulong value)
        {
            if(value == 0)
                return "0";
            System.Text.StringBuilder b = new System.Text.StringBuilder();
            while(value != 0)
            {
                b.Insert(0 , ( ( value & 1 ) == 1 ) ? '1' : '0');
                value >>= 1;
            }
            return b.ToString();
        }
        static void Main()
        {
            ulong input = ulong.Parse(Console.ReadLine());

            StringBuilder  bitsHack = new StringBuilder(ConvertToBinary(input).PadLeft(64,'0'));
            bitsHack.Replace("111" , "222");
            bitsHack.Replace("000" , "111");
            bitsHack.Replace("222" , "000");

            ulong output = Convert.ToUInt64(bitsHack.ToString(),2);
            Console.WriteLine(output);

        }
    }
}