无限极子孙分类统计某个用户的层级子孙各有哪些 各有多少

在统计某个节点下有多少子孙节点，可以采用之前写的递归方式处理，当然觉得递归太复杂  可以采用循环解决，这里提供一个例子

 代码如下：

<?php
$tree=array(
    array("id"=>"1",  "name"=>"用户1" ,  "father_id"=>"0"),
    array("id"=>"2",  "name"=>"用户2" ,  "father_id"=>"1"),
    array("id"=>"3",  "name"=>"用户3" ,  "father_id"=>"2"),
    array("id"=>"4",  "name"=>"用户4" ,  "father_id"=>"3"),
    array("id"=>"5",  "name"=>"用户5" ,  "father_id"=>"1"),
    array("id"=>"6",  "name"=>"用户6" ,  "father_id"=>"5"),
    array("id"=>"7",  "name"=>"用户7" ,  "father_id"=>"6"),
    array("id"=>"8",  "name"=>"用户8" ,  "father_id"=>"3"),
    array("id"=>"9",  "name"=>"用户9" ,  "father_id"=>"4"),
    array("id"=>"10", "name"=>"用户10" , "father_id"=>"5"),
    array("id"=>"11", "name"=>"用户11" , "father_id"=>"6"),
    array("id"=>"12", "name"=>"用户12" , "father_id"=>"7"),
    array("id"=>"13", "name"=>"用户13" , "father_id"=>"2"),
    array("id"=>"14", "name"=>"用户14" , "father_id"=>"13"),
    array("id"=>"15", "name"=>"用户15" , "father_id"=>"2"),
    array("id"=>"16", "name"=>"用户16" , "father_id"=>"17"),
    array("id"=>"17", "name"=>"用户17" , "father_id"=>"5"),
    array("id"=>"18", "name"=>"用户18" , "father_id"=>"17"),
    array("id"=>"19", "name"=>"用户19" , "father_id"=>"18"),
    array("id"=>"20", "name"=>"用户20" , "father_id"=>"20"),
    array("id"=>"21", "name"=>"用户21" , "father_id"=>"3"),
    array("id"=>"22", "name"=>"用户22" , "father_id"=>"21"),
    array("id"=>"23", "name"=>"用户23" , "father_id"=>"6"),
    array("id"=>"24", "name"=>"用户24" , "father_id"=>"23"),
    array("id"=>"25", "name"=>"用户25" , "father_id"=>"9"),
);

foreach ($tree as $key => $value)
{
    $user_list[$value['id']]=$value['name'];
    $father_link[$value['father_id']][]=$value['id'];
}

function get_level_son($father_link=array(),$user_id=0,$level=1)
{
    $father_list=array($user_id);
    for ($i=0; $i < $level; $i++)
    {
        $tmp_father=array();
        foreach ($father_list as $key => $v)
        {
            if(isset($father_link[$v]))
            {
                $tmp_father=array_unique(array_merge($tmp_father,$father_link[$v]));//找子孙
            }
        }
        $father_list=$tmp_father;//将子孙赋值给父亲
    }
    return $father_list;
}
echo '<link href="https://cdn.bootcss.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" rel="stylesheet">';
echo "<div class='container'><table class='table table-striped table-bordered table-hover table-condensed' style='80%;'>
<thead><tr><td>用户</td><td>1级子孙数量</td><td>1级子孙</td><td>2级子孙数量</td><td>2级子孙</td><td>3级子孙数量</td><td>3级子孙</td></tr></thead>";
echo "<tbody>";
foreach ($user_list as $key => $v)
{
    $list1=get_level_son($father_link,$key,1);
    $list2=get_level_son($father_link,$key,2);
    $list3=get_level_son($father_link,$key,3);
    $count1=count($list1);
    $count2=count($list2);
    $count3=count($list3);
    echo "<tr>
            <td>".$v."</td>
            <td>".$count1."</td>
            <td>".implode(",",$list1)."</td>
            <td>".$count2."</td>
            <td>".implode(",",$list2)."</td>
            <td>".$count3."</td>
            <td>".implode(",",$list3)."</td>
        </tr>";
}
echo "</tbody></table></div>";
?>

运行效果如图：