Online PHP editor | refs for sdX8g

<?php $muLevelIds = []; $subjectLevelIds = [1,6,7,8]; $occLevelIds = [6,7]; var_dump(array_union($muLevelIds, $subjectLevelIds, $occLevelIds)); function array_union($muLevelIds, $subjectLevelIds, $occLevelIds) { $allLevelIds = [1,6,7,8,9]; $combined = array_intersect($allLevelIds, $muLevelIds, $subjectLevelIds, $occLevelIds); return array_intersect($allLevelIds, $combined); }