冒泡排序

$arr = [2,376,3,1,65,123,758,1234,7856,123];
//冒泡
//逐行对比，满足条件则交换
function bubbleSort($arrData,$sort = 'desc')
{
    if(empty($arrData)) return $arrData;

    //默认有序
    $isSorted = true;
    $nCount = count($arrData);
    for($i = 0; $i < $nCount; $i++) {

        //对比次数随着循环逐渐减少，因为后面的数据已经处理为有序
        for($j = 0; $j < ($nCount - $i - 1); $j++) {
            //执行判断
            $isChange = $sort == 'desc' ? $arrData[$j] < $arrData[$j+1] : $arrData[$j] > $arrData[$j+1];

            if($isChange) {
                //首次对比，判断是否有序
                $isSorted = false;

                $temp = $arrData[$j];
                $arrData[$j] = $arrData[$j+1];
                $arrData[$j+1] = $temp;
            }
        }

        if($isSorted) break;
    }

    return $arrData;
}
$arr = bubbleSort($arr,'asc');
print_r($arr);