PHP sorting algorithm? PHP sorting classic algorithm_PHP tutorial

This article will summarize some good PHP sorting algorithms for you. I hope these algorithms will be helpful to all students.

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代码如下

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1.冒泡算法,排序算法，由于在排序过程中总是小数往前放，大数往后放，相当于气泡往上升，所以称作冒泡排序 $array = array(a,f,c,b,e,h,j,i,g);     function maopao_fun($array){         if($len <= 1) { return $arr; } $count = count($array); for($i=0;$i<$count;$i++){ for($j=$count-1;$j>$i;$j--){                 if($array[$j] > $array[$j-1]){                     $tmp = $array[$j];                     $array[$j] = $array[$j-1];                     $array[$j-1] = $tmp;                 }             }         }         return $array;     }  2.快速排序, 快速排序（Quicksort）是对冒泡排序的一种改进。 由C. A. R. Hoare在1962年提出。它的基本思想是：通过一趟排序将要排序的数据分割成独立的两部分， 其中一部分的所有数据都比另外一部分的所有数据都要小，然后再按此方法对这两部分数据分别进行快速排序， 整个排序过程可以递归进行，以此达到整个数据变成有序序列。 function quickSort($arr){         $len = count($arr);         if($len <= 1) { return $arr; } $key = $arr[0]; $left_arr = array(); $right_arr = array(); for($i=1; $i<$len; $i++){ if($arr[$i] <= $key){ $left_arr[] = $arr[$i]; } else { $right_arr[] = $arr[$i]; } } $left_arr = quickSort($left_arr); $right_arr = quickSort($right_arr); return array_merge($left_arr, array($key), $right_arr); }

1. Bubble algorithm, sorting algorithm, because in the sorting process, small numbers are always placed forward and large numbers are placed backward, which is equivalent to bubbles rising, so it is called bubble sort

<🎜>$array = array(a,f,c,b,e,h,j,i,g);

<🎜> function maopao_fun($array){

<🎜> if($len <= 1) {

<🎜> return $arr;

<🎜> }

<🎜> $count = count($array);

<🎜> for($i=0;$i<$count;$i++){

<🎜> for($j=$count-1;$j>$i;$j--){

if($array[$j] > $array[$j-1]){                           $tmp = $array[$j];                         $array[$j] = $array[$j-1];                            $array[$j-1] = $tmp;                                                                                                                                                                                } } return $array; } 2. Quick sort,
Quicksort is an improvement on bubble sort.
Proposed by C. A. R. Hoare in 1962. Its basic idea is to divide the data to be sorted into two independent parts through one sorting pass.
All the data in one part is smaller than all the data in the other part, and then the two parts of the data are quickly sorted in this way,
The entire sorting process can be performed recursively, so that the entire data becomes an ordered sequence. function quickSort($arr){ $len = count($arr); if($len <= 1) {

<🎜> return $arr;

<🎜> }

<🎜> $key = $arr[0];

<🎜> $left_arr = array();

<🎜> $right_arr = array();

<🎜> for($i=1; $i<$len; $i++){

<🎜> If($arr[$i] <= $key){

<🎜> $left_arr[] = $arr[$i];

<🎜>                                                                                           <🎜>                     $right_arr[] = $arr[$i];

<🎜>           }

<🎜> }

<🎜> $left_arr = quickSort($left_arr);

<🎜> $right_arr = quickSort($right_arr);

<🎜> return array_merge($left_arr, array($key), $right_arr);

<🎜> }

3.Select sort
Each pass selects the smallest (or largest) element from the data elements to be sorted,
The order is placed at the end of the sorted array until all data elements to be sorted are arranged. Selection sort is an unstable sorting method

The code is as follows

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代码如下	复制代码
function select_sort($arr){ $count = count($arr); for($i=0; $i<$count; $i++){ for($j=$i+1; $j<$count; $j++){ if ($arr[$i] > $arr[$j]){                  $tmp = $arr[$i];                  $arr[$i] = $arr[$j];                  $arr[$j] = $tmp;              }          }      }      return $arr;  }

function select_sort($arr){

$count = count($arr);

for($i=0; $i<$count; $i++){

for($j=$i+1; $j<$count; $j++){

if ($arr[$i] > $arr[$j]){

代码如下	复制代码
function insert_sort($arr){          $count = count($arr);          for($i=1; $i<$count; $i++){ $tmp = $arr[$i]; $j = $i - 1; while($arr[$j] > $tmp){                  $arr[$j+1] = $arr[$j];                  $arr[$j] = $tmp;                  $j--;              }          }          return $arr;      }         $arr = array(49,38,65,97,76,13,27);      print_r(insert_sort($arr));

$tmp = $arr[$i]; $arr[$i] = $arr[$j]; $arr[$j] = $tmp;          }  }   } return $arr; }

4. Insertion sort Starting from the first element, the element can be considered to have been sorted Take out the next element and scan from back to front in the sorted element sequence If the element (sorted) is larger than the new element, move the element to the next position Repeat step 3 until you find the position where the sorted element is less than or equal to the new element Insert the new element into the next position Repeat step 2

The code is as follows	Copy code
function insert_sort($arr){ $count = count($arr); for($i=1; $i<$count; $i++){ <🎜> <🎜> $tmp = $arr[$i]; <🎜> <🎜> $j = $i - 1; <🎜> <🎜> while($arr[$j] > $tmp){ $arr[$j+1] = $arr[$j]; $arr[$j] = $tmp; $j--;          }  }   return $arr; } $arr = array(49,38,65,97,76,13,27); print_r(insert_sort($arr));

PHP implementation of four sorting algorithms

1) The basic idea of ​​Insertion Sort is:
Each time a record to be sorted is inserted into the appropriate position in the previously sorted sub-file according to its key size, until all records are inserted.
2) The basic idea of ​​Selection Sort is:
In each pass, the record with the smallest keyword is selected from the records to be sorted and placed at the end of the sorted sub-file until all records are sorted.
3) The basic idea of ​​bubble sort is:
Compare the keywords of the records to be sorted pairwise, and if it is found that the order of the two records is reversed, they will be exchanged until there are no records in the reverse order.
4) Quick sort is essentially the same as bubble sort, and is an application of exchange sort. So the basic idea is the same as the bubble sort above.

代码如下

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 /** * Four sorting algorithm designs (PHP) * * 1) The basic idea of ​​​​Insertion Sort is: Each time a record to be sorted is inserted into the appropriate position in the previously sorted sub-file according to its key size, until all records are inserted. 2) The basic idea of ​​Selection Sort is: In each pass, the record with the smallest keyword is selected from the records to be sorted, and the order is placed at the end of the sorted sub-file until all records are sorted. 3) The basic idea of ​​bubble sorting is: Compare the keywords of the records to be sorted pairwise. If it is found that the order of the two records is reversed, they will be exchanged until there are no records in the reverse order. 4) Quick sort is essentially the same as bubble sort, and is an application of exchange sort. So the basic idea is the same as the bubble sort above. * * @author quanshuidingdang ​*/ class Sort {  private $arr  = array();   private $sort = 'insert';  private $marker = '_sort';    private $debug = TRUE;    /** * Constructor * * @param array For example: $config = array (             'arr' => array(22,3,41,18), //Array values ​​that need to be sorted 'Sort' = & gt; 'insert', // Possibly value: Insert, Select, Bubble, Quick            'debug' => TRUE                                                                                                                                                                                                                           . ) ​*/  public function __construct($config = array()) {   if ( count($config) > 0) {    $this->_init($config);   }  }    /** * Get sorted results ​*/  public function display() {   return $this->arr;  }    /** * Initialization * * @param array * @return bool ​*/  private function _init($config = array()) {   //参数判断   if ( !is_array($config) OR count($config) == 0) {    if ($this->debug === TRUE) {     $this->_log("sort_init_param_invaild");    }    return FALSE;   }      //初始化成员变量   foreach ($config as $key => $val) {    if ( isset($this->$key)) {     $this->$key = $val;    }   }      //调用相应的成员方法完成排序   $method = $this->sort . $this->marker;   if ( ! method_exists($this, $method)) {    if ($this->debug === TRUE) {     $this->_log("sort_method_invaild");    }    return FALSE;   }      if ( FALSE === ($this->arr = $this->$method($this->arr)))    return FALSE;   return TRUE;  }    /** * Insertion sort * * @param array * @return bool ​*/  private function insert_sort($arr) {   //参数判断   if ( ! is_array($arr) OR count($arr) == 0) {    if ($this->debug === TRUE) {     $this->_log("sort_array(insert)_invaild");    }    return FALSE;   }      //具体实现   $count = count($arr);   for ($i = 1; $i < $count; $i++) {    $tmp = $arr[$i];    for($j = $i-1; $j >= 0; $j--) {      if($arr[$j] > $tmp) {      $arr[$j+1] = $arr[$j];      $arr[$j] = $tmp;     }    }   }   return $arr;  }    /** *Select sort * * @param array * @return bool ​*/  private function select_sort($arr) {   //参数判断   if ( ! is_array($arr) OR count($arr) == 0) {    if ($this->debug === TRUE) {     $this->_log("sort_array(select)_invaild");    }    return FALSE;   }      //具体实现   $count = count($arr);   for ($i = 0; $i < $count-1; $i++) {    $min = $i;    for ($j = $i+1; $j < $count; $j++) {     if ($arr[$min] > $arr[$j])  $min = $j;    }    if ($min != $i) {     $tmp = $arr[$min];     $arr[$min] = $arr[$i];     $arr[$i] = $tmp;    }   }   return $arr;  }    /** * Bubble sort * * @param array * @return bool ​*/  private function bubble_sort($arr) {   //参数判断   if ( ! is_array($arr) OR count($arr) == 0) {    if ($this->debug === TRUE) {     $this->_log("sort_array(bubble)_invaild");    }    return FALSE;   }      //具体实现   $count = count($arr);   for ($i = 0; $i < $count; $i++) {    for ($j = $count-1; $j > $i; $j--) {     if ($arr[$j] < $arr[$j-1]) {      $tmp = $arr[$j];      $arr[$j] = $arr[$j-1];      $arr[$j-1] = $tmp;     }    }   }   return $arr;   }    /** * Quick sort * * @param array * @return bool ​*/  private function quick_sort($arr) {   //具体实现   if (count($arr) <= 1) return $arr;   $key = $arr[0];   $left_arr = array();   $right_arr = array();   for ($i = 1; $i < count($arr); $i++){    if ($arr[$i] <= $key)     $left_arr[] = $arr[$i];    else     $right_arr[] = $arr[$i];   }   $left_arr = $this->quick_sort($left_arr);   $right_arr = $this->quick_sort($right_arr);   return array_merge($left_arr, array($key), $right_arr);  }    /** * Logging ​*/  private function _log($msg) {   $msg = 'date[' . date('Y-m-d H:i:s') . '] ' . $msg . 'n';   return @file_put_contents('sort_err.log', $msg, FILE_APPEND);  } } /*End of file sort.php*/ /*Location htdocs/sort.php */

http://www.bkjia.com/PHPjc/632898.htmlwww.bkjia.comtruehttp://www.bkjia.com/PHPjc/632898.htmlTechArticle本文章来给大家总结几个不错的php排序算法，希望这些算法对各位同学会有所帮助哦。 代码如下 复制代码 1.冒泡算法,排序算法，由于在排...