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<?php declare(strict_types=1); $items = [ (object)['id' => 0, 'name' => "root"], (object)['id' => 1, 'parentId' => 0, 'name' => "foo"], (object)['id' => 2, 'parentId' => 1, 'name' => "bar"], (object)['id' => 3, 'parentId' => 1, 'name' => "qux"], (object)['id' => 4, 'parentId' => 3, 'name' => "zip"], (object)['id' => 5, 'parentId' => 4, 'name' => "baz"] ]; $itemsById = []; foreach ($items as $item) { $itemsById[$item->id] = $item; } // --- foreach ($itemsById as $id => $item) { if (isset($item->parentId)) { $itemsById[$item->parentId]->children[] = $item; } } $root = $itemsById[0]; var_dump($root);
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
object(stdClass)#1 (3) { ["id"]=> int(0) ["name"]=> string(4) "root" ["children"]=> array(1) { [0]=> object(stdClass)#2 (4) { ["id"]=> int(1) ["parentId"]=> int(0) ["name"]=> string(3) "foo" ["children"]=> array(2) { [0]=> object(stdClass)#3 (3) { ["id"]=> int(2) ["parentId"]=> int(1) ["name"]=> string(3) "bar" } [1]=> object(stdClass)#4 (4) { ["id"]=> int(3) ["parentId"]=> int(1) ["name"]=> string(3) "qux" ["children"]=> array(1) { [0]=> object(stdClass)#5 (4) { ["id"]=> int(4) ["parentId"]=> int(3) ["name"]=> string(3) "zip" ["children"]=> array(1) { [0]=> object(stdClass)#6 (3) { ["id"]=> int(5) ["parentId"]=> int(4) ["name"]=> string(3) "baz" } } } } } } } } }
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
Warning: Unsupported declare 'strict_types' in /in/Qe4PY on line 2 object(stdClass)#1 (3) { ["id"]=> int(0) ["name"]=> string(4) "root" ["children"]=> array(1) { [0]=> object(stdClass)#2 (4) { ["id"]=> int(1) ["parentId"]=> int(0) ["name"]=> string(3) "foo" ["children"]=> array(2) { [0]=> object(stdClass)#3 (3) { ["id"]=> int(2) ["parentId"]=> int(1) ["name"]=> string(3) "bar" } [1]=> object(stdClass)#4 (4) { ["id"]=> int(3) ["parentId"]=> int(1) ["name"]=> string(3) "qux" ["children"]=> array(1) { [0]=> object(stdClass)#5 (4) { ["id"]=> int(4) ["parentId"]=> int(3) ["name"]=> string(3) "zip" ["children"]=> array(1) { [0]=> object(stdClass)#6 (3) { ["id"]=> int(5) ["parentId"]=> int(4) ["name"]=> string(3) "baz" } } } } } } } } }

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98.27 ms | 2659 KiB | 4 Q