class Program
    {
        static void Main()
        {
            // You can also pass in any Function() that matches the delegate signature
            MyMainMethod(5, 3, AddTwoNumbers);
            MyMainMethod(5, 3, SubtractTwoNumbers);
            MyMainMethod(5, 3, MultiplyTwoNumbers);
            MyMainMethod(5, 3, DivideTwoNumber);
        }

        private static void MyMainMethod(double number1, double number2, Func<double, double, double> funcToCall)
        {
            Console.WriteLine("Startinging computation");
            var totalTime = 0.0;
            var watch = new Stopwatch();
            watch.Start();

            // This is where delegate rock!! Think a need
            // to call duplicate code with thousands of lines
            var result = funcToCall(number1, number2);

            watch.Stop();
            totalTime = watch.ElapsedMilliseconds;
            Console.WriteLine($"It took {totalTime}, milliseconds to compute result: {result}.");
        }

        static double AddTwoNumbers(double a, double b) { return a + b; }
        static double SubtractTwoNumbers(double a, double b) { return a - b; }
        static double MultiplyTwoNumbers(double a, double b) { return a * b; }
        static double DivideTwoNumber(double a, double b) { return a / b; }
    }