Online PHP editor | refs for hfDAN

<?php $leaders = [1,4,8,13]; $members = [2,3,5,6,7,9,10,11,12]; $result = []; $lastMember = null; foreach ($members as $member) { if ($lastMember === null || $lastMember !== $member - 1) { unset($ref); $result[array_shift($leaders)] = &$ref; } $ref[] = $lastMember = $member; } foreach ($leaders as $leader) { $result[$member] = null; } var_export($result);