import java.awt.*;
import java.applet.AudioClip;

public class MathMan extends javax.swing.JApplet
    implements Runnable {

    AudioClip[] number = new AudioClip[11];
    AudioClip plus;
    AudioClip equals;
    int sum, num1, num2;
    Thread runner;

    public void start() {
         if (runner == null) {
             runner = new Thread(this);
             runner.start();
         }
    }

    public void stop() {
        if (runner != null)
            runner = null;
    }

    public void init() {
        equals = getAudioClip(getCodeBase(), "equals.wav");
        plus = getAudioClip(getCodeBase(), "plus.wav");
        for (int i = 0; i < number.length; i++)
            number[i] = getAudioClip(getCodeBase(),
                "number" + i + ".wav");
    }

    public void run() {
        Thread thisThread = Thread.currentThread();
        while (runner == thisThread) {
            sum = (int) Math.floor(Math.random() * 10 + 1);
            num2 = (int) Math.floor(Math.random() * sum);
            num1 = sum - num2;
            repaint();
            number[num1].play();
            pause(600);
            plus.play();
            pause(600);
            number[num2].play();
            pause(600);
            equals.play();
            pause(600);
            number[sum].play();
            pause(5000);
        }
   }

    public void paint(Graphics screen) {
        super.paint(screen);
        int width = getSize().width;
        int height = getSize().height;
        Graphics2D screen2D = (Graphics2D) screen;
        screen2D.setColor(Color.white);
        screen2D.fillRect(0, 0, width, height);
        screen2D.setColor(Color.black);
        Font dialog = new Font("Dialog", Font.BOLD, 48);
        screen2D.setFont(dialog);
        screen2D.drawString(num1 + " + " + num2 + " = " + sum,
            width / 2 - 100, height / 2 - 25);
    }

    private void pause(int duration) {
        try {
            Thread.sleep(duration);
        } catch (InterruptedException e) { }
    }
}