// <applet code="CalcApplet" width="250" height="100"></applet>

import javax.swing.*;
import java.awt.event.*;
import java.awt.*;

public class CalcApplet extends JApplet implements ActionListener {
    private JTextField text1 = new JTextField(10);
    private JTextField text2 = new JTextField(10);
    private JButton plusButton = new JButton("+");
    private JButton minusButton = new JButton("-");
    private JButton timesButton = new JButton("*");
    private JButton divideButton = new JButton("/");
    private JTextField svarstext = new JTextField(10);

    public void actionPerformed(ActionEvent event) {
	String s1 = text1.getText();
	String s2 = text2.getText();
	try {
	    double num1 = Double.parseDouble(s1);
	    double num2 = Double.parseDouble(s2);
	    String op = ((JButton)event.getSource()).getText();
	    double result = 0;
	    switch (op.charAt(0)) {
	    case '+': result = num1 + num2; break;
	    case '-': result = num1 - num2; break;
	    case '*': result = num1 * num2; break;
	    case '/': result = num1 / num2; break;
	    }
	    svarstext.setText(result + "");
	}
	catch (NumberFormatException exc) {
	    svarstext.setText("ERROR");
	}
    } // actionPerformed

    public void init() {
        plusButton.addActionListener(this);
        minusButton.addActionListener(this);
        timesButton.addActionListener(this);
        divideButton.addActionListener(this);
        Container cp = getContentPane();
        cp.setLayout(new FlowLayout());
        cp.add(text1);
        cp.add(text2);
        cp.add(plusButton);
        cp.add(minusButton);
        cp.add(timesButton);
        cp.add(divideButton);
        cp.add(svarstext);
    }

    public static void main(String[] args) {
        CalcApplet applet = new CalcApplet();
        JFrame frame = new JFrame("CalcApplet");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.getContentPane().add(applet);
        frame.setSize(250, 150);
        applet.init();
        applet.start();
        frame.setVisible(true);
    }
} // class CalcApplet