PHP 插入排序 -- 折半查找

 1 <?php
 2 namespace Test;
 3 
 4 $a = [0 =>3,4,5,1,11,9,27,27,18,20];
 5 
 6 function binaryInsertSort(array &$arr)
 7 {
 8     $guild = 0;  // 监视哨
 9     $arr = array_values($arr);
10     array_unshift($arr,$guild);
11     $len = count($arr);
12 
13     for($i = 2;$i < $len;$i++)
14     {
15         if($arr[$i-1] > $arr[$i])
16         {
17             $arr[0] = $arr[$i];
18             $low = 1;
19             $high = $i - 1;
20 
21             while($low <= $high)
22             {
23                 $mid = ($high + $low)/2;
24                 if($arr[$mid] > $arr[0])
25                 {
26                     $high = $mid - 1;
27                 }
28                 else
29                 {
30                     $low = $mid + 1;
31                 }
32             }
33 
34             for($j = $i;$j >= $high + 1; --$j)
35             {
36                 $arr[$j] = $arr[$j - 1];
37             }
38 
39             $arr[$high + 1] = $arr[0];
40         }
41     }
42     array_shift($arr);
43 }
44 
45 binaryInsertSort($a);
46 echo implode(‘,‘,$a);