using System;

​

public class A

{

    public void info_a()

    {

        Console.WriteLine("Class A");

    }

}

public class B: A

{

    public void info_b()

    {

        Console.WriteLine("Class B");

    }

}

public class C: A

{

    public void info_c()

    {

        Console.WriteLine("Class C");

    }

}

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hierarchical Inheritance: ");

        Console.WriteLine();

        A a1 = new A();

        a1.info_a();

        Console.WriteLine("---------");

        B b1 = new B();

        b1.info_b();

        b1.info_a();

        Console.WriteLine("---------");

        C c1 = new C();

        c1.info_c();

        c1.info_a();

        Console.ReadLine();

    }

}