[php] 数据结构&算法(PHP描述) 快速排序 quick sort

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肖奔 2012-07-02 09:44:06

文章标签 开发者手机应用手机开发天翼社区天翼空间 文章分类 PHP 后端开发

1 <?php 2 /** 3 * 快速排序 quick sort 4 * 5 **/ 6 7 function sort_quick($arrData) { 8 if(empty($arrData) || !is_array($arrData)) return false; 9 10 $flag = $arrData[0];11 $len = count($arrData) - 1;12 if($len == 0) return $arrData; // 如果只有一个数据的数组直接返回13 14 $arrLeft = array();15 $arrRight = array();16 $len_l = 0;17 $len_r = 0;18 for($i = 1; $i <= $len;$i++) {19 if($arrData[$i] < $flag) {20 $arrLeft[$len_l] = $arrData[$i]; // 小于的放左边21 $len_l++;22 } else {23 $arrRight[$len_r] = $arrData[$i]; // 大于等于的放右边24 $len_r++;25 } 26 }27 28 // 合并数组29 $arrResult = array();30 if($len_l) {31 $arrLeft = sort_quick($arrLeft);32 for($i = 0;$i <= $len_l - 1; $i++ ) {33 $arrResult[$i] = $arrLeft[$i]; 34 }35 }36 $arrResult[$len_l] = $flag;37 $len_l++;38 if($len_r) {39 $arrRight = sort_quick($arrRight);40 for($i = 0;$i <= $len_r - 1; $i++ ) {41 $arrResult[$len_l] = $arrRight[$i];42 $len_l++;43 }44 }45 echo "== ",$flag," ========================================== ";46 echo "data : ",print_r($arrData)," ";47 echo "filter left: ",print_r($arrLeft)," ";48 echo "filter right: ",print_r($arrRight)," "; 49 echo "return : ",print_r($arrResult)," "; 50 51 return $arrResult;52 }53 //$list = array(4,3,2,1,5,7,3,7);54 $list = array(4,51,6,73,2,5,9,33,50,3,4,6,1,4,67);55 $list = sort_quick($list);56 echo "<pre>";print_r($list);