using System;

​

​

   public class Program

    {

        public static void Main()

        {           

            Console.WriteLine("for:");

            for(int i=1;i<= 32768;i=i*2){

                Console.Write("{0} ",i);

            }

            Console.WriteLine("\nwhile:");

            int j = 1;

            while (j <= 32768){

                Console.Write("{0} ",j);

                j = j*2;

            }

            Console.WriteLine("\ndo-while:");

            int k = 1;

            do{

                Console.Write("{0} ",k);

                k = k*2;

            }while (k <= 32768);

        }

    }