快速排序

<?php// 快速排序// 时间复杂度：O(nlog2n)function __quickSort(&$arr, $p, $q){$low = $p;$high = $q;$base_value = $arr[$low]; //基准值/*while(true) {while ($low < $high && $base_value <= $arr[$high])$high--;if($low >= $high) break;$arr[$low++] = $arr[$high];while ($low < $high && $arr[$low] <= $base_value)$low++;if($low >= $high) break;$arr[$high--] = $arr[$low];}*/while($low < $high) {// 越过不小于基准值的数据while($arr[$high] >= $base_value && $high > $low)$high--;if($low < $high) {$arr[$low++] = $arr[$high];// 越过小于基准值的数据while($arr[$low] <= $base_value && $low < $high)$low++;if($low < $high)$arr[$high--] = $arr[$low];}}$arr[$low] = $base_value;if($p < $low - 1) __quickSort($arr, $p, $low - 1);if($q > $high + 1) __quickSort($arr, $high + 1, $q);}function quickSort(&$arr) {__quickSort($arr, 0, count($arr) - 1);}