在线运行phphttp://www.compileonline.com/execute_php_online.php

 1 <?php 2 function swap( &$a, &$b ) 3 { 4     $c = $a; 5     $a = $b; 6     $b = $c; 7 } 8  9 /**10 * quick sort11 * ascend12 * in-place13 */14 function quick_sort( &$a )15 {16     $s = count( $a ); // size of a17     if ( $s < 2 ) return;18     $i = 0; // index of pivot, for tracking pivot19     $pivot = $a[$i];20     $l = 0; // swap listener, if listens no swap, sort fini21 22     // swap those smaller than pivot to the left23     for ( $m = 0; $m < $s; $m++ )24     {25         if ( $a[$m] < $a[$i] )26         {27             swap( $a[$m], $a[$i] );28             $i = $m;29             $l++;30         }31     }32 33     // swap those larger than pivot to the right34     for ( $n = 0; $n < $i; $n++)35     {36         if ( $a[$n] > $a[$i] )37         {38             swap( $a[$n], $a[$i] );39             $i = $n;40             $l++;41         }42     }43 44     if ( $l == 0 ) return;45     else $l = 0;46     quick_sort( $a );47 }48 49 $arr = range( 9, 0 );50 quick_sort( $arr );51 echo implode( ', ', $arr );52 ?>