using System;

public class Program

{

    static void Main(string[] args)

        {

            hola();

            Console.WriteLine("adios!");

            Console.WriteLine(duplicar (3));

        }

​

       static void hola() {

​

            Console.WriteLine("Hola!");

            Console.WriteLine("Hola!");

       }

           static double duplicar (double numero){

​

           return numero*2;

   }

​

}