using System;

public class shape

{

    public virtual void draw()

    {

        Console.WriteLine("drawing..");

    }

}

public class rectangle : shape

{

    public override void draw()

    {

        Console.WriteLine("drawing rectangle...");

    }

}

public class circle : shape

{

    public override void draw()

    {

        Console.WriteLine("drawing circle..");

    }

}

public class Testpolymorphism

{

    public static void Main()

    {

        shape s;

        s=new shape();

        s.draw();

        s=new rectangle();

        s.draw();

        s=new circle();

        s.draw();

    }

}