PHP implements merge sort (merge sort)--analysis of algorithm principles

Merge sort: The time complexity is ~O(nlogn)--also known as Merge sort

The merge sort method is to merge two (or more) ordered lists into a new ordered list ,

That is, the sequence to be sorted is divided into several ordered subsequences, and then the ordered subsequences are merged into an overall ordered sequence.

<?php $arrStoreList = array(3,2,4,1,5);
$sort = new Merge_sort();
$sort->stableSort($arrStoreList, function ($a, $b) {    // function ($a, $b)匿名函数
            return $a require no action.
        if (count($array) 

Output result: Array ( [0] => 5 [1] => 4 [2] => 3 [3] => 2 [4] => 1)

Analysis of algorithm principles: The key is to understand the principle of recursive calls and their return functions

The above introduces the implementation of merge sort (merge sort) in PHP - analysis of algorithm principles, including require aspects. I hope it will be helpful to friends who are interested in PHP tutorials.