using System;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

    }

}

​

public class Circle

{

    protected Double radius;

    public Circle(Double circleradius)

    {

        setRadius(circleradius);

    }

​

    public void setRadius(double circleRadius)

    {

        radius = circleRadius;

    }

​

    public double getRadius()

    {

        return radius;

    }

​

    public double calcArea()

    {

        return Math.PI * radius * radius;

    }

​

    public virtual double calcVolume()

    {

        return 0.0;

    }

}

​

public class Cylinder : Circle

{

    protected double height;

    public Cylinder(double cylHeight, double circleRadius): base(circleRadius)

    {

        base.setRadius(circleRadius);

        setHeight(cylHeight);

    }

​

    public void setHeight(double cheight)

    {

        height = cheight;

    }

​

    public double getHeight()

    {

        return height;

    }

​

    public override double calcVolume()

    {

        return base.calcArea() * height;

    }

}