csharp

public class A { public A() { Console.WriteLine("A"); }

public virtual void One()
{
    Console.WriteLine("One of A");
}

public virtual void Two()
{
    Console.WriteLine("Two of A");
    this.One();
}

public  virtual void Four()
{
    Console.WriteLine ("Four of A");
    this.Two();
}

} //end of class A

public class B : A { public B() { Console.WriteLine("B"); }

public override void One()
{
    Console.WriteLine("One of B");
}

public override void Two()
{
    Console.WriteLine("Two of B");
}

public void Three()
{
    Console.WriteLine("Three of B");
    base.Two();
}

} //end of class B

public class C : B { public override void Four() { Console.WriteLine ("Four of C"); } } //end of class C

public class Test { public static void Main(string [] args) { // כאן יופיעו הפקודות שבסעיפים להלן } }