Online PHP editor | refs for Ck1VH

<?php $comments = [ 1 => ['content' => "The first comment", 'parent' => 0], 2 => ['content' => "The second comment", 'parent' => 0], 3 => ['content' => "Reply of first comment", 'parent' => 1], 4 => ['content' => "Another reply of first comemnt", 'parent' => 1], 5 => ['content' => "Reply of a reply of the first comment", 'parent' => 4] ]; foreach($comments as $id => &$c) { if (isset($comments[$c['parent']])) { $comments[$c['parent']]['comments'][$id] =& $c; unset($comments[$id]); } } var_dump($comments);