using System;

using System.Collections;

public class Program

{

    static public void Swap(int x, int y) 

        {

            Stack numbers = new Stack();

            numbers.Push(x);

            numbers.Push(y);

            Console.WriteLine("The value of the 1st variable: " + numbers.Peek());

            numbers.Pop();

            Console.WriteLine("The value of the 2nd variable: " + numbers.Peek());

            numbers.Pop();      

        }

​

        static public void Main(string[] args)

        {

            //Assumed that user enters an input in a correct format

            Console.Write("Please give a number as 1st variable: ");

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

​

            Console.Write("Please give a number as 2nd variable: ");

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

​

            Swap(firstNumber, secondNumber);

        }

}