快速排序
<?php
$a = array(2,13,42,34,56,23,67,365,87665,54,68,3);
function quickSort($a) {$len = count($a);if($len < 2) {return $a;}$left = $right = array();$m = $a[0];for($i = 1; $i < $len; $i++) {if($a[$i] < $m) {array_push($left, $a[$i]);} else {array_push($right, $a[$i]);}}$left = quickSort($left);$right = quickSort($right);return array_merge($left, array($m), $right);
}
print_r(quickSort($a));