This most probably has been answered before but can't come up with the right keys to research it. I want to dynamically create a hash with multiple dimensions (number of dimensions dynamically increase) for example:

$data {$a}{$b}
$data {$a}{$b}{$c}
$data {$d}{$e}
[download]

So as the script is running I could add more dimensions to the initial hash using a subroutine called given the initial  $data{$a} . How do I do that? and how would I read the hash to get the keys and values if I don't know the dimension of the hash. Thank you.