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

public class Savings extends java.applet.Applet 
		implements ActionListener
{
    double savings, payment, rate, year, lastyear;
    DoubleField savingsF, paymentF, rateF, lastyearF;
    Button b1;
    public void init ()
    {
	paymentF = new DoubleField(20);
	paymentF.setLabel("Payment");
	rateF = new DoubleField(20);
	rateF.setLabel("Increment rate");
	lastyearF = new DoubleField(20);
	lastyearF.setLabel("Total Years");
	b1 = new Button("Compute");
       	b1.addActionListener(this);
	savingsF = new DoubleField(20);
	savingsF.setLabel("Savings");
	add(paymentF);
	add(rateF);
	add(lastyearF);
	add(b1);
	add(savingsF);
	paymentF.setDouble(0);
	rateF.setDouble(0);
	lastyearF.setDouble(0);
	savingsF.setDouble(0);
    }

    public void actionPerformed(ActionEvent event)
    {	
	Object cause = event.getSource();
	if (cause == b1)
	{
	    savings = 0;
            year = 1;	   
	    payment = paymentF.getDouble();
            rate = rateF.getDouble();
            lastyear = lastyearF.getDouble();
            while (year <= lastyear)
	    {
                savings = savings + (savings * rate) + payment;
                year = year + 1;
            }
	    savingsF.setDouble(savings);
	}
    }
}