using System;

public class Program

{

    public static void Main()

    {

        start:

        Console.WriteLine("introduce initial value");

        int n1 = Convert.ToInt32(Console.ReadLine());

        Console.WriteLine("introduce limit");

        int n2 = Convert.ToInt32(Console.ReadLine());

        Console.WriteLine("introduce increment");

        int inc = Convert.ToInt32(Console.ReadLine());

        //check if the values are corret for the statement

        if (n1 < n2 && inc > 0 && inc <= ( n2 - n1))

        {

            for( int i = n1; i <= n2; i += inc)

            {

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

            }

        }

        else 

        {

            Console.WriteLine("please introduce the values again.");

            goto start;

        }

    }

}