import awb.*;
import java.awt.*;
import java.awt.event.*;

public class CylinderVolumes extends java.applet.Applet
            implements ActionListener
{
    double r, V;
    DoubleField rF, VF;
    Button b1;
    
    public void init()
    {
        rF = new DoubleField(20);
        rF.setLabel("Radius");
        b1 = new Button("Compute");
        b1.addActionListener(this);
        VF = new DoubleField(20);
        VF.setLabel("Volume");
        add(rF);
        add(b1);
        add(VF);
        r = 1.0;
        rF.setDouble(r);
    }

    public void actionPerformed(ActionEvent event)
    {
	Object cause = event.getSource();
        if (cause == b1)
        {
		V = 500.0 * r - 3.14159 * r * r * r;
                rF.setDouble(r);
                VF.setDouble(V);
                r = r + 1.0;
        }
    }
}