把以下程式碼轉換成多維陣列

$ret = [
'version'=>1,
'app.sys.auth.user'=>1,
'app.sys.auth.admin'=>'admin',
'app.menu.article'=>'article',
];

轉換多維陣列後:

Array
(
    [version] => 1
    [app] => Array
        (
            [sys] => Array
                (
                    [auth] => Array
 

                        (
                            [user] => 1
                            [admin] => admin
                        )
                )
            [menu] => Array
                (
                    [article] => article
                )
        )
)

實現程式碼:

$strings
 
 = [
'version'=>1,
'app.sys.auth.user'=>1,
'app.sys.auth.admin'=>'admin',
'app.menu.article'=>'article',
];

function format($string,$val) {
    $arr = explode('.', $string);
    $result = null;
    // 彈出最後一個元素
    for($i = count($arr) - 1; $i >= 0; $i--) {
        if($result === null) {
            $result
 
 = array($arr[$i]=>$val);
        } else {
            $result = array($arr[$i]=>$result);
        }
    }
    return $result;
}

$result = array();
foreach($strings as $key=>$val) {
    $result = array_merge_recursive($result, format($key,$val));
}