三维数怎么合并子数组

<code>$result_arr = array();
foreach($arr as $key => $data){
    foreach($data as $val) {
        $second_key = key($val);
        $result_arr[$key][$second_key] = $val[$second_key];
    }
}</code>

<code>$arr = array(
'初级' =>array(
    0=>array(
        2=>95,
        ),
    1=>array(
        3 => 423,
        )
    ),
'二级' => array(
    0=>array(
        4=>22,
        ),
    1=>array(
        5 => 43,
        )
    ),
);

foreach ($arr as $key => $value) {
    foreach ($value as $k => $v) {
        foreach ($v as $ks => $vs) {
            $arrs[$key][$ks] = $vs;
        }
        
    }
}
var_dump($arr);
var_dump($arrs);</code>