java的一些代码...

我觉得写得还可以，累死了，50分不容易啊
你还可以修改一下
import java.applet.Applet;
import javax.swing.*;
import javax.swing.border.*;

public class Calculator extends JApplet implements ActionListener
{
private final String[] KEYS={"7","8","9","/","sqrt",
"4","5","6","*","%",
"1","2","3","-","1/x",
"0","+/-",".","+","="
};
private final String[] COMMAND={"Backspace","CE","C"};
private final String[] M={" ","MC","MR","MS","M+"};
private JButton keys[]=new JButton[KEYS.length];
private JButton commands[]=new JButton[COMMAND.length];
private JButton m[]=new JButton[M.length];
private JTextField display =new JTextField("0");

//