51.Delegate with argument with return value in C#

 using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace simple_delegate

{

    public delegate double Demo(double a, double b); 

    class Program

    {

        static double mul(double x, double y)

        { return x * y;  }

        static double add(double x, double y)

        { return x + y; }

        static void Main(string[] args)

        {

            Demo obj_del1 = new Demo(mul);

            Demo obj_del2 = new Demo(add);

            Console.Write("Enter First Value : ");

            double d1 = Convert.ToDouble(Console.ReadLine());

            Console.Write("Enter Second Value : ");

            double d2 = Convert.ToDouble(Console.ReadLine());

            double ans1 = obj_del1(d1, d2);

            Console.WriteLine("Multiplication : " + ans1);

            double ans2 = obj_del2(d1, d2);

            Console.WriteLine("Addition : " + ans2);

            Console.Read();

        }

    }

}

OUTPUT:

Enter First Value : 2

Enter Second Value : 5

Multiplication : 10

Addition : 7