function quicksort(&$data, $beg, $end) 
02 { 
03 if ($end > $beg) { 
04 $piv = $data[$beg]; 
05 $k = $beg + 1; 
06 $r = $end; 
07 while ($k
08 if ($data[$k]
09 $k++; 
10 } else { 
11 $tmp = $data[$k]; 
12 $data[$k] = $data[$r]; 
13 $data[$r] = $tmp; 
14 $r--; 
15 } 
16 } 
17 if ($data[$k] >= $piv) { 
18 $k--; 
19 } 
20 $tmp = $data[$k]; 
21 $data[$k] = $data[$beg]; 
22 $data[$beg] = $tmp; 
23 quicksort($data, $beg, $k); 
24 quicksort($data, $r, $end); 
25 } 
26 } 
27   
28 function quicksort2(&$data) 
29 { 
30 $stack = array(); 
31 array_push($stack, array(0, count($data) - 1)); 
32 while (list($beg, $end) = array_pop($stack)) { 
33 if ($end > $beg) { 
34 $piv = $data[$beg]; 
35 $k = $beg + 1; 
36 $r = $end; 
37 while ($k
38 if ($data[$k]
39 $k++; 
40 } else { 
41 $tmp = $data[$k]; 
42 $data[$k] = $data[$r]; 
43 $data[$r] = $tmp; 
44 $r--; 
45 } 
46 } 
47 if ($data[$k] >= $piv) { 
48 $k--; 
49 } 
50 $tmp = $data[$k]; 
51 $data[$k] = $data[$beg]; 
52 $data[$beg] = $tmp; 
53 array_push($stack, array($beg, $k)); 
54 array_push($stack, array($r, $end)); 
55 } 
56 } 
57 } 
58   
59 $data = array(7,6,6,3,8,1,8,1,9,1,3,11,51,1,25); 
60 //selectsort($data); 
61 //insertsort($data); 
62 quicksort2($data);