using System;

public class example

{

    public delegate int Deleadd(int a, int b);

    public delegate int Delesub(int a, int b);

    public static void Main(string[] args)

    {

        Results Results = new Results();

        Deleadd sum = new Deleadd(Results.sum);

        Delesub sub = new Delesub(Results.sub);

        int a = sum(50, 20);

        int b = sub(50, 20);

        Console.WriteLine("Addition is: " + a);

        Console.WriteLine("Subtraction is: " + b);

        Console.ReadLine();

    }

}

public class Results

{

    public int sum(int a, int b)

    {

        return a + b;

    }

    public int sub(int a, int b)

    {

        return a - b;

    }

}