test

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

namespace Test
{
    class Program
    {
        static void Main(string[] args)
        {
            int dec = 1000;
            String result = "";

            while (dec > 0)
            {
                int bin = dec % 2;
                dec /= 2;
                result = bin + result;
            }

            Console.WriteLine(result);
            Console.WriteLine(result.Length);
            while (result.Length % 4 != 0)
            {
                result = "0" + result;
            }
            Console.WriteLine(result);
            Console.WriteLine(result.Length);

            int count = 0;
            for (int i = 0; i < result.Length; i++)
            {
                if (count == 4)
                {
                    result = result.Insert(i, " ");
                    count = 0;
                }

                if (result[i].ToString() != " ")
                {
                    count++;
                }
            }

                Console.WriteLine(result);

        }
    }
}