PHP数组到树数组

Question

I have a problem I cannot fix. I have 2 arrays and a string. The first array contains the keys the second one should use. The first one is like this:

Array
(
    [0] => foo
    [1] => bar
    [2] => hello
)

Now I need a PHP code that converts it to the second array:

Array
(
    [foo] => Array
        (
            [bar] => Array
                (
                    [hello] => MyString
                )
        )
)

The number of items is variable.

Can someone please tell me how to do this?

Answer 1

You should use references to solve this problem:

$a = array (0 => 'foo', 1 => 'bar', 2 => 'hello' );

$b = array();
$ptr = &$b;
foreach ($a as $val) {
    $ptr[$val] = Array();
    $ptr = &$ptr[$val];
}
$ptr = 'MyString';
var_dump($b);