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<?php $menu = array( array(1,3,'Wurm 1.1', 2, 10), array(2,6,'Vogel 2.1', 2, 30), array(3,0,'Tiger 1', 1, 10), array(4,6,'Hund 2.2', 2, 40), array(5,3,'Katze 1.2', 2, 11), array(6,0,'Pferd 2', 1, 20), array(7,1,'Baer 1.1.1', 3, 0), array(8,3,'Schwein 1.3', 2, 12), array(9,4,'Esel 2.2.1', 3, 0), ); // Algorithmus hier /* steps: 1. sort items by levelId and sortId - finished 2. get max levelId value 'x' = iterations - ...that seems to be not the way to go. better way would be recursion for each element and search for children belonging to the current menuId.... 3. ... */ const IDX_ID = 0; const IDX_PARENT = 1; const IDX_SORT = 4; $result = array(); foreach ($menu as $key => $row){ $levelId[$key] = $row[3]; $sortId[$key] = $row[4]; } array_multisort($levelId, SORT_ASC, $sortId, SORT_ASC, $menu); $parentId = 4; $items = array_filter($menu, function($item) use ($parentId) { return $item[IDX_PARENT] == $parentId; }); var_dump($items); $target = array( array(3,0,'Tiger 1', 1, 10), array(1,3,'Wurm 1.1', 2, 10), array(7,1,'Baer 1.1.1', 3, 0), array(5,3,'Katze 1.2', 2, 11), array(8,3,'Schwein 1.3', 2, 12), array(6,0,'Pferd 2', 1, 20), array(2,6,'Vogel 2.1', 2, 30), array(4,6,'Hund 2.2', 2, 40), array(9,4,'Esel 2.2.1', 3, 0), ); //var_dump($result == $target);