| 1 |  |  | <?php | 
            
                                                                                                            
                            
            
                                    
            
            
                | 2 |  |  | /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 3 |  |  |  * DataStructures for PHP | 
            
                                                                                                            
                            
            
                                    
            
            
                | 4 |  |  |  * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 5 |  |  |  * @link      https://github.com/SiroDiaz/DataStructures | 
            
                                                                                                            
                            
            
                                    
            
            
                | 6 |  |  |  * @copyright Copyright (c) 2017 Siro Díaz Palazón | 
            
                                                                                                            
                            
            
                                    
            
            
                | 7 |  |  |  * @license   https://github.com/SiroDiaz/DataStructures/blob/master/README.md (MIT License) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 8 |  |  |  */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 9 |  |  | namespace DataStructures\Trees; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 10 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 11 |  |  | use DataStructures\Trees\Traits\CountTrait; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 12 |  |  | use DataStructures\Trees\Interfaces\TreeInterface; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 13 |  |  | use DataStructures\Trees\Interfaces\BinaryNodeInterface; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 14 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 15 |  |  | /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 16 |  |  |  * BinaryTreeAbstract | 
            
                                                                                                            
                            
            
                                    
            
            
                | 17 |  |  |  *  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 18 |  |  |  * BinaryTreeAbstract class is an abstract class that implements | 
            
                                                                                                            
                            
            
                                    
            
            
                | 19 |  |  |  * common binary trees methods. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 20 |  |  |  * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 21 |  |  |  * @author Siro Diaz Palazon <[email protected]> | 
            
                                                                                                            
                            
            
                                    
            
            
                | 22 |  |  |  */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 23 |  |  | abstract class BinaryTreeAbstract implements TreeInterface { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 24 |  |  |     use CountTrait; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 25 |  |  |     protected $root; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 26 |  |  |     protected $size = 0; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 27 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 28 |  |  |     abstract public function createNode($key, $data, $parent = null, $left = null, $right = null); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 29 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 30 |  |  |      * Checks if the tree is empty. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 31 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 32 |  |  |      * @return boolean true if is empty, else false. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 33 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 34 |  |  |     public function empty() : bool { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 35 |  |  |         return $this->root === null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 36 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 37 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 38 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 39 |  |  |      * Returns the tree size. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 40 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 41 |  |  |      * @return int the length | 
            
                                                                                                            
                            
            
                                    
            
            
                | 42 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 43 |  |  |     public function size() : int { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 44 |  |  |         return $this->size; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 45 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 46 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 47 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 48 |  |  |      * Inserts data in the correct position. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 49 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 50 |  |  |      * @param integer|string $key the key used to store. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 51 |  |  |      * @param mixed $data the data to store. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 52 |  |  |      * @param bool $update if false the node isn't updated | 
            
                                                                                                            
                            
            
                                    
            
            
                | 53 |  |  |      *  else if the key matches is updated. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 54 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 55 |  |  |     public function put($key, $data, $update = false) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 56 |  |  |         $newNode = $this->createNode($key, $data); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 57 |  |  |          | 
            
                                                                                                            
                            
            
                                    
            
            
                | 58 |  |  |         if($this->root === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 59 |  |  |             $this->root = &$newNode; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 60 |  |  |             $this->size++; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 61 |  |  |             return; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 62 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 63 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 64 |  |  |         $parentNode = null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 65 |  |  |         $current = &$this->root; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 66 |  |  |         while($current !== null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 67 |  |  |             $parentNode = &$current; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 68 |  |  |             if($key < $current->key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 69 |  |  |                 $current = &$current->left; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 70 |  |  |             } else if($key > $current->key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 71 |  |  |                 $current = &$current->right; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 72 |  |  |             } else { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 73 |  |  |                 if($update) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 74 |  |  |                     $current->data = $data; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 75 |  |  |                     return $newNode; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 76 |  |  |                 } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 77 |  |  |                 return; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 78 |  |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 79 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 80 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 81 |  |  |         $newNode->parent = &$parentNode; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 82 |  |  |         if($key < $parentNode->key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 83 |  |  |             $parentNode->left = &$newNode; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 84 |  |  |         } else { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 85 |  |  |             $parentNode->right = &$newNode; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 86 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 87 |  |  |         $this->size++; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 88 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 89 |  |  |         return $newNode; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 90 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 91 |  |  |      | 
            
                                                                                                            
                            
            
                                    
            
            
                | 92 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 93 |  |  |      * Creates a new node or updates it if already exists. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 94 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 95 |  |  |      * @param int|string $key the key. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 96 |  |  |      * @param mixed $data the data to be stored.  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 97 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 98 |  |  |     public function putOrUpdate($key, $data) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 99 |  |  |         $this->put($key, $data, true); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 100 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 101 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 102 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 103 |  |  |      * Retrieve the data stored in the tree. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 104 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 105 |  |  |      * @param int|string $key the key to identify the data. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 106 |  |  |      * @return mixed | 
            
                                                                                                            
                            
            
                                    
            
            
                | 107 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 108 |  |  |     public function get($key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 109 |  |  |         if($this->root === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 110 |  |  |             return null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 111 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 112 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 113 |  |  |         $node = $this->root; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 114 |  |  |         while($node !== null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 115 |  |  |             if($key < $node->key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 116 |  |  |                 $node = $node->left; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 117 |  |  |             } else if($key > $node->key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 118 |  |  |                 $node = $node->right; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 119 |  |  |             } else { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 120 |  |  |                 return $node->data; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 121 |  |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 122 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 123 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 124 |  |  |         return null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 125 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 126 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 127 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 128 |  |  |      * Returns the root node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 129 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 130 |  |  |      * @return DataStructures\Trees\Nodes\BinaryNodeInterface|null the root node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 131 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 132 |  |  |     public function getRoot() { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 133 |  |  |         return $this->root; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 134 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 135 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 136 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 137 |  |  |      * Looks for the node with the given key. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 138 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 139 |  |  |      * @param int|string $key the key used to look for. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 140 |  |  |      * @return bool true if was found. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 141 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 142 |  |  |     public function exists($key) : bool { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 143 |  |  |         // $this->_exists($this->root, $key); for recursive search | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 144 |  |  |         if($this->root === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 145 |  |  |             return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 146 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 147 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 148 |  |  |         if($this->root->key === $key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 149 |  |  |             return true; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 150 |  |  |         } else { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 151 |  |  |             $node = $this->root; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 152 |  |  |             while($node !== null) { | 
            
                                                                                                            
                            
            
                                                                    
                                                                                                        
            
            
                | 153 |  | View Code Duplication |                 if($key < $node->key) { | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 154 |  |  |                     $node = $node->left; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 155 |  |  |                 } else if($key > $node->key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 156 |  |  |                     $node = $node->right; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 157 |  |  |                 } else { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 158 |  |  |                     return true; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 159 |  |  |                 } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 160 |  |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 161 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 162 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 163 |  |  |         return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 164 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 165 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 166 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 167 |  |  |      * Method that retrieves true if found a node with the specified key. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 168 |  |  |      * It's the recursive version of exists method and it's used internally | 
            
                                                                                                            
                            
            
                                    
            
            
                | 169 |  |  |      * for traverse through a root node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 170 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 171 |  |  |      * @param DataStructures\Trees\Nodes\BinaryNodeInterface|null $node the root node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 172 |  |  |      * @param int|string $key the key used to look for. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 173 |  |  |      * @return bool true if exists a node with that key. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 174 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 175 |  |  |     private function _exists($node, $key) : bool { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 176 |  |  |         if($node === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 177 |  |  |             return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 178 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 179 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 180 |  |  |         if($node->key === $key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 181 |  |  |             return true; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 182 |  |  |         } else if($key < $node->key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 183 |  |  |             return $this->_exists($node->left, $key); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 184 |  |  |         } else if($key > $node->key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 185 |  |  |             return $this->_exists($node->right, $key); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 186 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 187 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 188 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 189 |  |  |     public function floor($key){} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 190 |  |  |     public function ceil($key){} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 191 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 192 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 193 |  |  |      * Gets the node with the minimum key. The most left and more bottom. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 194 |  |  |      *  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 195 |  |  |      * @return DataStructures\Trees\Nodes\BinaryNodeInterface|null the minum node or | 
            
                                                                                                            
                            
            
                                    
            
            
                | 196 |  |  |      *  null if the tree is empty. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 197 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 198 |  |  |     public function min() { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 199 |  |  |         if($this->root === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 200 |  |  |             return null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 201 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 202 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 203 |  |  |         if($this->root->left === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 204 |  |  |             return $this->root; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 205 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 206 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 207 |  |  |         $current = $this->root; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 208 |  |  |         while($current->left !== null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 209 |  |  |             $current = $current->left; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 210 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 211 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 212 |  |  |         return $current; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 213 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 214 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 215 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 216 |  |  |      * Gets the node with the maximum key. The most right and more bottom. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 217 |  |  |      *  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 218 |  |  |      * @return DataStructures\Trees\Nodes\BinaryNodeInterface|null the maximum node or | 
            
                                                                                                            
                            
            
                                    
            
            
                | 219 |  |  |      *  null if the tree is empty. | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 220 |  |  |      */ | 
            
                                                                        
                            
            
                                    
            
            
                | 221 |  |  |     public function max() { | 
            
                                                                        
                            
            
                                    
            
            
                | 222 |  |  |         if($this->root === null) { | 
            
                                                                        
                            
            
                                    
            
            
                | 223 |  |  |             return null; | 
            
                                                                        
                            
            
                                    
            
            
                | 224 |  |  |         } | 
            
                                                                        
                            
            
                                    
            
            
                | 225 |  |  |  | 
            
                                                                        
                            
            
                                    
            
            
                | 226 |  |  |         if($this->root->right === null) { | 
            
                                                                        
                            
            
                                    
            
            
                | 227 |  |  |             return $this->root; | 
            
                                                                        
                            
            
                                    
            
            
                | 228 |  |  |         } | 
            
                                                                        
                            
            
                                    
            
            
                | 229 |  |  |  | 
            
                                                                        
                            
            
                                    
            
            
                | 230 |  |  |         $node = $this->root; | 
            
                                                                        
                            
            
                                    
            
            
                | 231 |  |  |         while($node->right !== null) { | 
            
                                                                        
                            
            
                                    
            
            
                | 232 |  |  |             $node = $node->right; | 
            
                                                                        
                            
            
                                    
            
            
                | 233 |  |  |         } | 
            
                                                                        
                            
            
                                    
            
            
                | 234 |  |  |  | 
            
                                                                        
                            
            
                                    
            
            
                | 235 |  |  |         return $node; | 
            
                                                                        
                            
            
                                    
            
            
                | 236 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 237 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 238 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 239 |  |  |      * Returns the minimum node from a given node in position X. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 240 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 241 |  |  |      * @param DataStructures\Trees\Nodes\BinaryNodeInterface $node the start point. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 242 |  |  |      * @return DataStructures\Trees\Nodes\BinaryNodeInterface|null the minimum node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 243 |  |  |      */ | 
            
                                                                                                            
                            
            
                                                                    
                                                                                                        
            
            
                | 244 |  | View Code Duplication |     protected function getMinNode(BinaryNodeInterface $node = null) { | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 245 |  |  |         if($node === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 246 |  |  |             return null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 247 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 248 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 249 |  |  |         while($node->left !== null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 250 |  |  |             $node = $node->left; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 251 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 252 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 253 |  |  |         return $node; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 254 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 255 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 256 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 257 |  |  |      * Returns the maximum node from a given node in position X. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 258 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 259 |  |  |      * @param DataStructures\Trees\Nodes\BinaryNodeInterface $node the start point. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 260 |  |  |      * @return DataStructures\Trees\Nodes\BinaryNodeInterface|null the maximum node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 261 |  |  |      */ | 
            
                                                                                                            
                            
            
                                                                    
                                                                                                        
            
            
                | 262 |  | View Code Duplication |     protected function getMaxNode(BinaryNodeInterface $node = null) { | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 263 |  |  |         if($node === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 264 |  |  |             return null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 265 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 266 |  |  |          | 
            
                                                                                                            
                            
            
                                    
            
            
                | 267 |  |  |         while($node->right !== null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 268 |  |  |             $node = $node->right; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 269 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 270 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 271 |  |  |         return $node; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 272 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 273 |  |  |      | 
            
                                                                                                            
                            
            
                                    
            
            
                | 274 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 275 |  |  |      * Deletes the node with the minimum key and returns it. The most left and more bottom. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 276 |  |  |      *  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 277 |  |  |      * @param DataStructures\Trees\Nodes\BinaryNodeInterface|null if null takes the root. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 278 |  |  |      * @return DataStructures\Trees\Nodes\BinaryNodeInterface|null the minimum node or | 
            
                                                                                                            
                            
            
                                    
            
            
                | 279 |  |  |      *  null if the tree is empty. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 280 |  |  |      */ | 
            
                                                                                                            
                            
            
                                                                    
                                                                                                        
            
            
                | 281 |  | View Code Duplication |     public function deleteMin(BinaryNodeInterface $node = null) { | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 282 |  |  |         $node = $this->getMinNode($node ?? $this->root); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 283 |  |  |         if($node !== null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 284 |  |  |             $this->_delete($node); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 285 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 286 |  |  |          | 
            
                                                                                                            
                            
            
                                    
            
            
                | 287 |  |  |         return $node; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 288 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 289 |  |  |      | 
            
                                                                                                            
                            
            
                                    
            
            
                | 290 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 291 |  |  |      * Deletes the node with the maximum key and returns it. The most right and more bottom. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 292 |  |  |      *  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 293 |  |  |      * @param DataStructures\Trees\Nodes\BinaryNodeInterface|null if null takes the root. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 294 |  |  |      * @return DataStructures\Trees\Nodes\BinaryNodeInterface|null the maximum node or | 
            
                                                                                                            
                            
            
                                    
            
            
                | 295 |  |  |      *  null if the tree is empty. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 296 |  |  |      */ | 
            
                                                                                                            
                            
            
                                                                    
                                                                                                        
            
            
                | 297 |  | View Code Duplication |     public function deleteMax(BinaryNodeInterface $node = null) { | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 298 |  |  |         $node = $this->getMaxNode($node ?? $this->root); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 299 |  |  |         if($node !== null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 300 |  |  |             $this->_delete($node); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 301 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 302 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 303 |  |  |         return $node; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 304 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 305 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 306 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 307 |  |  |      * Deletes the node with the maximum key and returns it. The most right and more bottom. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 308 |  |  |      *  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 309 |  |  |      * @param DataStructures\Trees\Nodes\BinaryNodeInterface|null if null takes the root. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 310 |  |  |      * @return DataStructures\Trees\Nodes\BinaryNodeInterface|null the maximum node or | 
            
                                                                                                            
                            
            
                                    
            
            
                | 311 |  |  |      *  null if the tree is empty. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 312 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 313 |  |  |     public function delete($key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 314 |  |  |         $deleteNode = $this->search($key); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 315 |  |  |         if($deleteNode !== null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 316 |  |  |             $this->_delete($deleteNode); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 317 |  |  |             return $deleteNode; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 318 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 319 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 320 |  |  |         return null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 321 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 322 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 323 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 324 |  |  |      * Deletes the selected node if is not null and returns the node | 
            
                                                                                                            
                            
            
                                    
            
            
                | 325 |  |  |      * that replaces the deleted node. Also decrease the size of tree. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 326 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 327 |  |  |      * @param DataStructures\Trees\Nodes\BinaryNodeInterface|null The node to be deleted. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 328 |  |  |      * @return the node that replaces the deleted. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 329 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 330 |  |  |     protected function _delete(BinaryNodeInterface &$node) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 331 |  |  |         if($node !== null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 332 |  |  |             $nodeToReturn = null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 333 |  |  |             if($node->left === null) { | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 334 |  |  |                 $nodeToReturn = $this->replace($node, $node->right); | 
                            
                    |  |  |  | 
                                                                                        
                                                                                            
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 335 |  |  |             } else if($node->right === null) { | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 336 |  |  |                 $nodeToReturn = $this->replace($node, $node->left); | 
                            
                    |  |  |  | 
                                                                                        
                                                                                            
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 337 |  |  |             } else { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 338 |  |  |                 $successorNode = $this->getMinNode($node->right); | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 339 |  |  |                 if($successorNode->parent !== $node) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 340 |  |  |                     $this->replace($successorNode, $successorNode->right); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 341 |  |  |                     $successorNode->right = &$node->right; | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 342 |  |  |                     $successorNode->right->parent = &$successorNode; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 343 |  |  |                 } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 344 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 345 |  |  |                 $this->replace($node, $successorNode); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 346 |  |  |                 $successorNode->left = &$node->left; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 347 |  |  |                 $successorNode->left->parent = &$successorNode; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 348 |  |  |                 $nodeToReturn = &$successorNode; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 349 |  |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 350 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 351 |  |  |             $this->size--; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 352 |  |  |             return $nodeToReturn; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 353 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 354 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 355 |  |  |         return null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 356 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 357 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 358 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 359 |  |  |      * Replaces the node n to remove a new one k and links k with the parent | 
            
                                                                                                            
                            
            
                                    
            
            
                | 360 |  |  |      * of n. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 361 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 362 |  |  |      * @param DataStructures\Trees\Nodes\BinaryNodeInterface $nodeToReplace the node to remove. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 363 |  |  |      * @param DataStructures\Trees\Nodes\BinaryNodeInterface|null $newNode the newNode | 
            
                                                                                                            
                            
            
                                    
            
            
                | 364 |  |  |      *  to link with the $nodeToReplace parent. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 365 |  |  |      * @return DataStructures\Trees\Nodes\BinaryNodeInterface the new linked node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 366 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 367 |  |  |     protected function replace(&$nodeToReplace, &$newNode) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 368 |  |  |         if($nodeToReplace->parent === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 369 |  |  |             $this->root = &$newNode; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 370 |  |  |         } else if($nodeToReplace === $nodeToReplace->parent->left) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 371 |  |  |             $nodeToReplace->parent->left = &$newNode; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 372 |  |  |         } else if($nodeToReplace === $nodeToReplace->parent->right) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 373 |  |  |             $nodeToReplace->parent->right = &$newNode; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 374 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 375 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 376 |  |  |         if($newNode !== null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 377 |  |  |             $newNode->parent = &$nodeToReplace->parent; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 378 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 379 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 380 |  |  |         return $newNode; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 381 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 382 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 383 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 384 |  |  |      * Retrieves the node with the specified key. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 385 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 386 |  |  |      * @param int|string $key the key used to store. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 387 |  |  |      * @return DataStructures\Trees\Nodes\BinaryNodeInterface|null the node or null. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 388 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 389 |  |  |     public function search($key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 390 |  |  |         if($this->root === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 391 |  |  |             return null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 392 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 393 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 394 |  |  |         if($this->root->key === $key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 395 |  |  |             return $this->root; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 396 |  |  |         } else { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 397 |  |  |             $node = $this->root; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 398 |  |  |             while($node !== null) { | 
            
                                                                                                            
                            
            
                                                                    
                                                                                                        
            
            
                | 399 |  | View Code Duplication |                 if($key < $node->key) { | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 400 |  |  |                     $node = $node->left; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 401 |  |  |                 } else if($key > $node->key) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 402 |  |  |                     $node = $node->right; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 403 |  |  |                 } else { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 404 |  |  |                     return $node; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 405 |  |  |                 } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 406 |  |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 407 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 408 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 409 |  |  |         return null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 410 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 411 |  |  |      | 
            
                                                                                                            
                            
            
                                    
            
            
                | 412 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 413 |  |  |      * Returns true if is leaf the node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 414 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 415 |  |  |      * @param DataStructures\Trees\Nodes\BinaryNodeInterface|null $node default to null. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 416 |  |  |      * @return true if is leaf the node, is not null and their subtrees has no | 
            
                                                                                                            
                            
            
                                    
            
            
                | 417 |  |  |      *  pointers to successors. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 418 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 419 |  |  |     public function isLeaf($node) : bool { // BinaryTreeNode | 
            
                                                                                                            
                            
            
                                    
            
            
                | 420 |  |  |         return ($node !== null && $node->left === null && $node->right === null); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 421 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 422 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 423 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 424 |  |  |      * Checks if a node is root. New nodes that does not point to any other node | 
            
                                                                                                            
                            
            
                                    
            
            
                | 425 |  |  |      * also are called a root node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 426 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 427 |  |  |      * @param DataStructures\Trees\Nodes\BinaryNodeInterface|null $node default to null. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 428 |  |  |      * @return true if is root the node, is not null and their subtrees has no | 
            
                                                                                                            
                            
            
                                    
            
            
                | 429 |  |  |      *  pointers to successors. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 430 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 431 |  |  |     public function isRoot($node) : bool { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 432 |  |  |         return $node !== null && $node->parent === null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 433 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 434 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 435 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 436 |  |  |      * Traverse in preorder. This is: first visit the root, then | 
            
                                                                                                            
                            
            
                                    
            
            
                | 437 |  |  |      * the left subtree and finally the right subtree. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 438 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 439 |  |  |      * @param Callable|null $callback the callback function to apply to each | 
            
                                                                                                            
                            
            
                                    
            
            
                | 440 |  |  |      *  node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 441 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 442 |  |  |     public function preorder(Callable $callback = null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 443 |  |  |         $this->_preorder($this->root, $callback); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 444 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 445 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 446 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 447 |  |  |      * Private preorder traverse method that is recursive and is called by | 
            
                                                                                                            
                            
            
                                    
            
            
                | 448 |  |  |      * the public preorder method. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 449 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 450 |  |  |      * @param DataStructures\Trees\Nodes\BinaryNodeInterface|null $node. | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 451 |  |  |      * @param Callable|null $callback the callback function to apply to each | 
            
                                                                                                            
                            
            
                                    
            
            
                | 452 |  |  |      *  node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 453 |  |  |      */ | 
            
                                                                                                            
                            
            
                                                                    
                                                                                                        
            
            
                | 454 |  | View Code Duplication |     private function _preorder($node, Callable $callback = null) { | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 455 |  |  |         if($node === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 456 |  |  |             return; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 457 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 458 |  |  |         if($callback !== null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 459 |  |  |             call_user_func($callback, $node); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 460 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 461 |  |  |         $this->_preorder($node->left, $callback); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 462 |  |  |         $this->_preorder($node->right, $callback); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 463 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 464 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 465 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 466 |  |  |      * Traverse in inorder. This is: first visit the left subtree, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 467 |  |  |      * then the root and finally the right subtree. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 468 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 469 |  |  |      * @param Callable|null $callback the callback function to apply to each | 
            
                                                                                                            
                            
            
                                    
            
            
                | 470 |  |  |      *  node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 471 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 472 |  |  |     public function inorder(Callable $callback = null) { | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 473 |  |  |         $this->_inorder($this->root); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 474 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 475 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 476 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 477 |  |  |      * Private inorder traverse method that is recursive and is called by | 
            
                                                                                                            
                            
            
                                    
            
            
                | 478 |  |  |      * the public inorder method. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 479 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 480 |  |  |      * @param DataStructures\Trees\Nodes\BinaryNodeInterface|null $node. | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 481 |  |  |      * @param Callable|null $callback the callback function to apply to each | 
            
                                                                                                            
                            
            
                                    
            
            
                | 482 |  |  |      *  node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 483 |  |  |      */ | 
            
                                                                                                            
                            
            
                                                                    
                                                                                                        
            
            
                | 484 |  | View Code Duplication |     private function _inorder($node, Callable $callback = null) { | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 485 |  |  |         if($node === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 486 |  |  |             return; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 487 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 488 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 489 |  |  |         $this->_inorder($node->left, $callback); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 490 |  |  |         if($callback !== null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 491 |  |  |             call_user_func($callback, $node); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 492 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 493 |  |  |         $this->_inorder($node->right, $callback); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 494 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 495 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 496 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 497 |  |  |      * Traverse in postorder. This is: first visit the left subtree, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 498 |  |  |      * then the right subtree and finally the root. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 499 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 500 |  |  |      * @param Callable|null $callback the callback function to apply to each | 
            
                                                                                                            
                            
            
                                    
            
            
                | 501 |  |  |      *  node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 502 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 503 |  |  |     public function postorder(Callable $callback = null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 504 |  |  |         $this->_postorder($this->root, $callback); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 505 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 506 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 507 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 508 |  |  |      * Private postorder traverse method that is recursive and is called by | 
            
                                                                                                            
                            
            
                                    
            
            
                | 509 |  |  |      * the public postorder method. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 510 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 511 |  |  |      * @param DataStructures\Trees\Nodes\BinaryNodeInterface|null $node. | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 512 |  |  |      * @param Callable|null $callback the callback function to apply to each | 
            
                                                                                                            
                            
            
                                    
            
            
                | 513 |  |  |      *  node. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 514 |  |  |      */ | 
            
                                                                                                            
                            
            
                                                                    
                                                                                                        
            
            
                | 515 |  | View Code Duplication |     private function _postorder($node, Callable $callback = null) { | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 516 |  |  |         if($node === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 517 |  |  |             return; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 518 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 519 |  |  |         $this->_postorder($node->left, $callback); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 520 |  |  |         $this->_postorder($node->right, $callback); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 521 |  |  |         if($callback !== null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 522 |  |  |             call_user_func($callback, $node); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 523 |  |  |         } | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 524 |  |  |     } | 
            
                                                        
            
                                    
            
            
                | 525 |  |  | } | 
            
                        
Sometimes obsolete code just ends up commented out instead of removed. In this case it is better to remove the code once you have checked you do not need it.
The code might also have been commented out for debugging purposes. In this case it is vital that someone uncomments it again or your project may behave in very unexpected ways in production.
This check looks for comments that seem to be mostly valid code and reports them.