namespace example {
	public class Swap {
		public static int num1;
		public static int num2;

		public static void Main() {

			//get two inputs
			while(!int.TryParse(System.Console.ReadLine(), out num1)){
				System.Console.WriteLine("That was invalid input, enter a integer.");
			}
			while(!int.TryParse(System.Console.ReadLine(), out num2)){
				System.Console.WriteLine("That was invalid input, enter a integer.");
			}


			System.Console.WriteLine("1st Number: " + num1 + ", 2nd Number : " + num2);

			//swap values
			swapValues(ref num1, ref num2);

			System.Console.WriteLine("The value of the 1st variable: " + num1);
			System.Console.WriteLine("The value of the 2nd variable: " + num2);
		}


		//get two integer as parameter and swap them
		public static void swapValues(ref int num1, ref int num2) {

			num1 = num1 + num2;
			num2 = num1 - num2;
			num1 = num1 - num2;

		}
	}
}