using System;

public class Program

{

    public static void Main()

    {

        int cek; 

        for(int i = 20; i <50;i = i + 1)

        {

            cek = i % 2;

            if (cek == 1)

            {

                Console.WriteLine(i+"hitam");

            }

               else if(cek == 0 )

               {

                Console.WriteLine(i+"putih");

             }

        }

    }

}