- var_dump: documentation ( source)
- array_reverse: documentation ( source)
<?php
function cluster($array) {
$array = array_reverse($array);
foreach($array as $element) {
$newarray = [$element=>$newarray];
}
return $newarray;
}
var_dump(cluster(['A', 'B', 'C', 'D','E','F','G','H','I']));