//修正了一個BUG 
import java.awt.*; 
import java.awt.event.*; 

import javax.swing.*; 

public class BetGame extends JFrame implements ActionListener{ 
private final double fac = 5;//概率系數(shù),取值>=2, 越接近2越不易獲勝 
private JRadioButton a,b,c; 
private JLabel value; 
private JLabel rs; 
private JButton bet,exit; 
private JComboBox co; 
private int coin = 10000;; 

public BetGame(){ 
super("真錢游戲"); 
this.getContentPane().setLayout(null); 
value = new JLabel("資金:"+coin); 
value.setFont(new Font("simsun",Font.PLAIN,12)); 
value.setBounds(16,12,100,22); 
this.getContentPane().add(value); 

a=new JRadioButton("正面"); 
b=new JRadioButton("反面"); 
c=new JRadioButton("",true); 
ButtonGroup g = new ButtonGroup(); 
g.add(a);g.add(b);g.add(c); 

a.setBounds(16,48,68,25); 
b.setBounds(88,48,68,25); 
this.getContentPane().add(a); 
this.getContentPane().add(b); 

JLabel l = new JLabel("下注"); 
l.setBounds(16,88,48,25); 
this.getContentPane().add(l); 
co = new JComboBox(new String[]{"5","10","20","50","100","200","500","全部",}); 
co.setBounds(68,88,88,25); 
this.getContentPane().add(co); 

rs = new JLabel(); 
rs.setBounds(16,120,100,25); 
rs.setFont(value.getFont()); 
this.getContentPane().add(rs); 

bet = new JButton("開始"); 
bet.setBounds(16,158,68,25); 
bet.addActionListener(this); 
this.getContentPane().add(bet); 

exit=new JButton("離開"); 
exit.setBounds(95,158,68,25); 
exit.addActionListener(this); 
this.getContentPane().add(exit); 

this.setSize(198,238); 
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 

} 

public static void main(String[] args) { 
new BetGame().setVisible(true); 
} 

public void actionPerformed(ActionEvent e) { 
if(e.getSource()==bet){ 
if(coin<=0){ 
JOptionPane.showMessageDialog(this,"您的帳戶余額不足,請充值!"); 
return; 
} 
if(c.isSelected()){ 
JOptionPane.showMessageDialog(this, "請選擇正面或反面"); 
return; 
} 
int its = co.getItemCount(); 
int id = co.getSelectedIndex(); 
if(id<its-1) 
{ 
if(Integer.parseInt(co.getSelectedItem().toString())>coin){ 
JOptionPane.showMessageDialog(this,"您的投注額超過了您的余額!"); 
return; 
} 
} 
double rate = .5; 
rate-=id/(its*fac);//投注額越多中將概率相應降低 
System.out.println("獲勝概率 :"+rate); 
boolean win = Math.random()<rate; 
if(win){ 
if(id==its-1) 
coin*=2; 
else 
coin+=Integer.parseInt(co.getSelectedItem().toString()); 
} 
else{ 
if(id==its-1) 
coin=0; 
else 
coin-=Integer.parseInt(co.getSelectedItem().toString()); 
} 
rs.setText(win?a.isSelected()?"正面":"反面":a.isSelected()?"反面":"正面"); 
value.setText("資金:"+coin); 
// co.setSelectedIndex(0); 
// c.setSelected(true); 
} 
else 
System.exit(0); 
} 
}