How to implement common sorting in php

This article will introduce to you how to implement common sorting in PHP. It has certain reference value. Friends in need can refer to it. I hope it will be helpful to everyone.

$arr = [4,5,3,2,1,9,8,6,7];

Bubble sort

function maopao($arr)
{
    $len = count($arr);
    for ($i=1; $i <$len ; $i++) { 
        # code...
        for ($k=0; $k <($len-$i) ; $k++) { 
            # code...
            if ($arr[$k]>$arr[$k+1]) {
                # code...
                $v_k = $arr[$k];
                $arr[$k]=$arr[$k+1];
                $arr[$k+1]=$v_k;    
            }
        }
    }
    return $arr;
}

Quick sort

function kuaisu($arr)
{
    $len = count($arr);
    if ($len<=1) {
        # code...
        return $arr;
    }
    //选择基准元素
    $a = $arr[0];
    $left = $right = [];
    //循环
    for ($i=1; $i < $len; $i++) { 
        # code...
        if ($arr[$i]<$a) {
            # code...
            $left[]=$arr[$i];
        }else{
            $right[]=$arr[$i];
        }
    }
    $left = kuaisu($left);
    $right = kuaisu($right);
    return array_merge($left,[$a],$right);
}

Insertion sort

function insertSort($arr)
{
    $len = count($arr);
    for ($i=1; $i < $len; $i++) { 
        # code...
        $tmp = $arr[$i];
        for ($j=$i-1; $j >=0 ; $j--) { 
            # code...
            if ($tmp<$arr[$j]) {
                    # code...
                $arr[$j+1]=$arr[$j];
                $arr[$j]=$tmp;    
            }else{
                break;
            }    
        }
    }
    return $arr;
    }

Selection sort

function selectSort($arr)
{
    $len = count($arr);

    for ($i=0; $i < $len; $i++) { 
        # code...
        $p=$i;

        for ($j=$i+1; $j < $len; $j++) { 
            # code...
            if ($arr[$p]>$arr[$j]) {
                # code...
                $p=$j;
            }

        }

        $tmp = $arr[$p];
        $arr[$p]=$arr[$i];
        $arr[$i]=$tmp;

    }

    return $arr;
}

Recommended learning: php video tutorial

The above is the detailed content of How to implement common sorting in php. For more information, please follow other related articles on the PHP Chinese website!