static void Main(string[] args) { // Variables int num1 = 0; int num2 = 0; bool salir = false; int opcion; bool invop = false; while (!salir) { Console.Clear(); Console.WriteLine("Welcome to the calculator"); Console.WriteLine(""); Console.WriteLine("Ingrese 2 numeros"); num1 = Int32.Parse(Console.ReadLine()); num2 = Int32.Parse(Console.ReadLine()); Console.WriteLine(""); Console.WriteLine("1 - Suma"); Console.WriteLine("2 - Resta"); Console.WriteLine("3 - Multiplicacion"); Console.WriteLine("4 - Division"); Console.WriteLine("0 - Salir"); Console.WriteLine(""); while (!invop) { opcion = Int32.Parse(Console.ReadLine()); switch (opcion) { case 1: Console.WriteLine(Math.Suma(num1, num2)); invop = true; break; case 2: Console.WriteLine(Math.Resta(num1, num2)); invop = true; break; case 3: Console.WriteLine(Math.Multiplicacion(num1, num2)); invop = true; break; case 4: Console.WriteLine(Math.Division(num1, num2)); invop = true; break; case 0: salir = true; invop = true; break; default: Console.WriteLine("Opcion invalida"); break; } } Console.ReadLine(); } }