PHP One level deeper in array each loop made

Question

I\'m trying to loop through one array, adding a new level to another array each time. Let me illustrate - variable $arr\'s values are different each time

$ar         


        

Answer 1

function add_inner_array(&$array, $index) {
    if(isset($array[$index])) return true;
    else {
        $array[$index] = array();
        return true;
    }
}

$a = array(1,5,6);
$index = array();
$pass =& $index;
foreach($a as $k) {
    add_inner_array($pass, $k);
    $pass =& $pass[$k];
}