//filename: Calculator2000.java
import java.awt.*;
import java.awt.event.*;
import java.applet.*;

public class Calculator2000 extends Applet implements ActionListener
{
  public TextField in1, in2, out;
  public Button plus, minus, times, div;
    
  public void init()
  {
    Panel p1, p2;
    setLayout(new GridLayout(2, 1, 10, 10));
        
    in1 = new TextField(); 
    in2 = new TextField();
    out = new TextField();
    out.setEditable(false);
    p1 = new Panel(new GridLayout(4, 1, 2, 2));
    p1.add(in1); p1.add(in2); p1.add(out); add(p1);
        
    plus = new Button("plus"); minus = new Button("minus");
    times = new Button("times"); div = new Button("divide");
    p2 = new Panel(new GridLayout(1, 5, 10, 10));
    p2.add(plus); p2.add(minus); p2.add(times); p2.add(div); add(p2);
        
    plus.addActionListener(this); minus.addActionListener(this);
    times.addActionListener(this); div.addActionListener(this);
  }
    
  public void actionPerformed(ActionEvent e)
  {
    String ac = e.getActionCommand();
    double x1 = new Double(in1.getText()).doubleValue();
    double x2 = new Double(in2.getText()).doubleValue();
    double result = 0;
        
    if (ac.equals("plus")) result = x1 + x2;
    else if (ac.equals("minus")) result = x1 - x2;
    else if (ac.equals("times")) result = x1 * x2;
    else if (ac.equals("divide")) result = x1 / x2;
    out.setText(result + "");
  }
}