using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine(" ");

        Console.WriteLine("a = 7");

        Console.WriteLine("b = 13");

        Console.WriteLine("c = 25");

        Console.WriteLine("b = a");

        Console.WriteLine("c = b");

        Console.WriteLine("a = c");

        Console.WriteLine(" ");

        Console.WriteLine(" ");

        Console.WriteLine("Primer paso.- Declarar variables");

        Double a = 7;

        Double b = 13;

        Double c = 25;

        Double d = b;

        Console.WriteLine(" ");

        Console.WriteLine("Segundo paso.- Intercambiar los valores");

        Console.WriteLine(" ");

        b = a;

        a = c;

        c = d;

        Console.WriteLine("Tercer paso.- Imprimir los resultados");

        Console.WriteLine(" ");

        Console.WriteLine("b = " + b);

        Console.WriteLine("c = " + c);

        Console.WriteLine("a = " + a);

    }

}