每瓶啤酒2元，2个空酒瓶或4个瓶盖可换1瓶啤酒。10元最多可喝多少瓶啤酒？ php

//根据题意设定初始变量值
//然后 一个while循环去操作
//每换得一个瓶子，换的那个减去要做相应的数目
//然后喝了啤酒后， 各数量加1
//直到不符合要求。跳出循环
 1 class Beer{
 2 
 3     protected $uni_gai      = 4;    //每4个瓶盖1瓶
 4     protected $uni_bottle   = 2;    //每两个瓶子换1瓶
 5     protected $uni_beer     = 2;    //每瓶2块钱
 6     protected $rs           = array();//存取结果
 7     protected $total        = 0;      //当前买了啤酒的数量
 8     protected $gai          = 0;      //当前有多少个啤酒
 9     protected $empty_bottle = 0;      //空瓶子
10 
11     public function __construct($money){
12         $cur = $money / $this->uni_beer;
13         $this->total        = $cur;
14         $this->gai          = $cur;
15         $this->empty_bottle = $cur;
16     }
17 
18     public function run(){
19         while($this->gai > 0 || $this->empty_bottle > 0){
20             if($this->gai >= $this->uni_gai){
21                 $this->deal_num('gai');
22             }
23             if($this->empty_bottle >= $this->uni_bottle){
24                 $this->deal_num('empty_bottle');
25             }
26 
27             $this->check_overflow();
28         }
29         return $this->rs;
30     }
31 
32     public function deal_num($type){
33         if($type == 'gai'){
34             $this->gai -= $this->uni_gai;
35         }else{
36             $this->empty_bottle -= $this->uni_bottle;
37         }
38         $this->gai++;
39         $this->empty_bottle++;
40         $this->total++;
41     }
42     public function check_overflow(){
43         if($this->gai < $this->uni_gai && $this->empty_bottle < $this->uni_bottle){
44             $this->rs['gai']          = $this->gai;
45             $this->rs['total']        = $this->total;
46             $this->rs['empty_bottle'] = $this->empty_bottle;
47             $this->gai                = 0;
48             $this->empty_bottle       = 0;
49         }
50     }
51     public function _print(){
52         echo 'gai:', $this->gai;
53         echo '<br>';
54         echo 'empty_bottle:', $this->empty_bottle;
55         echo '<br>';
56         echo 'total', $this->total;
57         echo '<hr>';
58     }
59 }
60 
61 $peer = new Beer(10);
62 $rs   = $peer->run();
63 print_r($rs);