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<?php class CategoryTree { protected $roots = []; public function addCategory($category, $parent) { if ($this->categoryExists($this->roots, $category)) { throw new InvalidArgumentException(); } if ($parent === null) { $this->tree[$category] = []; return; } $node = $this->findNode($parent, $this->root); if(!isset($node)) { throw new InvalidArgumentException(); } $node[$category] = []; } public function getChildren($parent) { $node = $this->findNode($parent, $this->root); if(!isset($node)) { throw new InvalidArgumentException(); } return array_keys($node); } public function findNode($node, &$root) { if (in_array($node, array_keys($root))) { return $root[$node]; } foreach ($root as $n) { return $this->findNode($node, $n); } } public function categoryExists($nodes, $category) { $exists = false; foreach($nodes as $node) { if (in_array($category, $this->getChildren($node))) { return true; } $exists = $this->categoryExists($node, $category); } return $exists; } } // For testing purposes (do not submit uncommented): $c = new CategoryTree; $c->addCategory('A', null); $c->addCategory('B', 'A'); $c->addCategory('C', 'A'); //echo implode(',', $c->getChildren('A'));
Output for 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Deprecated: Creation of dynamic property CategoryTree::$tree is deprecated in /in/NbPdm on line 14 Deprecated: Creation of dynamic property CategoryTree::$root is deprecated in /in/NbPdm on line 18 Fatal error: Uncaught TypeError: array_keys(): Argument #1 ($array) must be of type array, null given in /in/NbPdm:35 Stack trace: #0 /in/NbPdm(35): array_keys(NULL) #1 /in/NbPdm(18): CategoryTree->findNode('A', NULL) #2 /in/NbPdm(58): CategoryTree->addCategory('B', 'A') #3 {main} thrown in /in/NbPdm on line 35
Process exited with code 255.
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28
Fatal error: Uncaught TypeError: array_keys(): Argument #1 ($array) must be of type array, null given in /in/NbPdm:35 Stack trace: #0 /in/NbPdm(35): array_keys(NULL) #1 /in/NbPdm(18): CategoryTree->findNode('A', NULL) #2 /in/NbPdm(58): CategoryTree->addCategory('B', 'A') #3 {main} thrown in /in/NbPdm on line 35
Process exited with code 255.
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Warning: array_keys() expects parameter 1 to be array, null given in /in/NbPdm on line 35 Warning: in_array() expects parameter 2 to be array, null given in /in/NbPdm on line 35 Warning: Invalid argument supplied for foreach() in /in/NbPdm on line 38 Fatal error: Uncaught InvalidArgumentException in /in/NbPdm:20 Stack trace: #0 /in/NbPdm(58): CategoryTree->addCategory('B', 'A') #1 {main} thrown in /in/NbPdm on line 20
Process exited with code 255.
Output for 5.5.24 - 5.5.35, 5.6.8 - 5.6.28
Warning: array_keys() expects parameter 1 to be array, null given in /in/NbPdm on line 35 Warning: in_array() expects parameter 2 to be array, null given in /in/NbPdm on line 35 Warning: Invalid argument supplied for foreach() in /in/NbPdm on line 38 Fatal error: Uncaught exception 'InvalidArgumentException' in /in/NbPdm:20 Stack trace: #0 /in/NbPdm(58): CategoryTree->addCategory('B', 'A') #1 {main} thrown in /in/NbPdm on line 20
Process exited with code 255.

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