How to implement various sorting algorithms with php

This article mainly introduces how to use PHP to implement various sorting algorithms, such as bubble sorting, exchange sorting, selection sorting, insertion sorting, and quick sorting. Different sorting algorithms can be selected according to the actual situation. Efficiency also makes a difference. The important thing is to understand the algorithm first, and then implementation will be a matter of course. Interested friends can refer to it, I hope it will be helpful to everyone.

Bubble sorting:

<?php
    function BubbleSort（$arr）{
    $num = count（$arr）；
    for（$i=1;$i<$num;$i++）{
    for（$j=$num-1;$j>=$i;$j--）{
    if（$arr[$j]<$arr[$j-1]）{
    $iTemp = $arr[$j-1];
    $arr[$j-1] = $arr[$j];
    $arr[$j] = $iTemp;
    }
    }
    }
    return $arr;
    }
    ?>

Exchange sorting:

<?php
    function ExchangeSort（$arr）{
    $num = count（$arr）；
    for（$i=0;$i<$num-1;$i++）{
    for（$j=$i+1;$j<$num;$j++）{
    if（$arr[$j]<$arr[$i]）{
    $iTemp = $arr[$i];
    $arr[$i] = $arr[$j];
    $arr[$j] = $iTemp;
    }
    }
    }
    return $arr;
    }
    ?>

Selection sorting:

<?php
    function SelectSort（$arr）{
    $num = count（$arr）；
    for（$i=0;$i<$num-1;$i++）{
    $iTemp = $arr[$i];
    $iPos = $i;
    for（$j=$i+1;$j<$num;$j++）{
    if（$arr[$j]<$iTemp）{
    $iTemp = $arr[$j];
    $iPos = $j;
    }
    }
    $arr[$iPos] = $arr[$i];
    $arr[$i] = $iTemp;
    }
    return $arr;
    }
    ?>

Insertion sorting:

<?php
    function InsertSort（$arr）{
    $num = count（$arr）；
    for（$i=1;$i<$num;$i++）{
    $iTemp = $arr[$i];
    $iPos = $i-1;
    while（（$iPos>=0） && （$iTemp<$arr[$iPos]））{
    $arr[$iPos+1] = $arr[$iPos];
    $iPos--;
    }
    $arr[$iPos+1] = $iTemp;
    }
    return $arr;
    }
    ?>

Quick sort:

<?php
    function QuickSort（$arr）{
    $num = count（$arr）；
    $l=$r=0;
    for（$i=1;$i<$num;$i++）{
    if（$arr[$i] < $arr[0]）{
    $left[] = $arr[$i];
    $l++;
    }else{
    $right[] = $arr[$i];
    $r++;
    }
    }
    if（$l > 1）{
    $left = QuickSort（$left）；
    }
    $new_arr = $left;
    $new_arr[] = $arr[0];
    if（$r > 1）{
    $right = QuickSort（$right）；
    }
    for（$i=0;$i<$r;$i++）{
    $new_arr[] = $right[$i];
    }
    return $new_arr;
    }
    $arr = array（7,1,6,5,2）；
    $arr_new = QuickSort（$arr）；
    ?>

Related recommendations:

Example of direct insertion sort algorithm implemented in Python

The six commonly used JS sorting algorithms and Comparison

Implementation and efficiency analysis of four sorting algorithms in PHP [bubble sort, insertion sort, selection sort and quick sort]

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