Online PHP editor | refs for U0lYP

<?php $a = ['net' => ['domain' => ['www' => null, 'shit' => null]]]; function walk(array $a, $stem = '') { $result = []; foreach ($a as $k => $v) { $current = $stem ? "$stem.$k" : $k; if (is_array($v)) { $result = array_merge($result, walk($v, $current)); } else { $result[] = $current; } } return $result; } foreach (walk($a) as $domain) { print "$domain\n"; }