Data structure of PHP 9: stores binary trees, creates binary trees, and performs basic operations on binary trees, and traverses binary tree algorithms.

Data structure of PHP 9: stores binary trees, creates binary trees, and performs basic operations on binary trees, and traverses binary tree algorithms.

Create a binary tree and basic operations PHP stores a binary tree. create a binary tree and perform basic operations on the binary tree to traverse the binary tree algorithm.

 * @ Version $ Id: BinaryTree. class. php, v 1.0 13:33:00 uw Exp * @ copyright©2011, xudianyang */header ('content-type: text/html; charset = gb2312 '); // the implementation of PHP on the fifth stack of the PHP Data structure and the basic operations on the stack can be found in this class of include_once (". /StackLinked. class. php "); // you can find the include_once ('. /QueueLinked. class. php '); class BTNode {// left subtree "pointer" public $ mLchild = null; // right subtree "pointer" public $ mRchild = null; // public $ mData = null; // indicates the left flag field. if the value is 1, mLchild points to the left child of the node, 2 indicates that "pointing" the node directly precursor public $ intLeftTag = null; // the right flag field. if it is 1, it indicates mRchi. Ld points to the right child of the node. 2 indicates that the node is directed to the public $ intRightTag = null;} class BinaryTree {// root node public $ mRoot; // traverse the input binary tree data in the first order public $ mPBTdata = null;/*** constructor, initialize the establishment of a binary tree ** @ param array $ btdata traverse the data of the input binary tree in the first order, one-dimensional array, each element represents a binary tree node value, expand the node value to ''[string with a length of 0] * @ return void */public function _ construct ($ btdata = array ()) {$ this-> mPBTdata = $ btdata; $ this-> mRoot = null; $ this-> getPreorderTraversalCreate ($ this-> mRoot );} /*** create a binary tree in the first traversal mode ** @ p Aram BTNode binary tree node, passed by reference * @ return void */public function getPreorderTraversalCreate (& $ btnode) {$ elem = array_shift ($ this-> mPBTdata ); if ($ elem = '') {$ btnode = null;} else if ($ elem = null) {return ;} else {$ btnode = new BTNode (); $ btnode-> mData = $ elem; $ this-> getPreorderTraversalCreate ($ btnode-> mLchild ); $ this-> getPreorderTraversalCreate ($ btnode-> mRchild) ;}}/*** determines whether the binary tree is empty. ** @ return boolean: true is returned if the binary tree is not empty. otherwise, fa is returned. Lse **/public function getIsEmpty () {if ($ this-> mRoot instanceof BTNode) {return false;} else {return true ;}} /*** leave the binary tree blank ** @ return void */public function setBinaryTreeNull () {$ this-> mRoot = null ;} /*** traverse the binary tree in sequence ** @ param BTNode $ the root node in the rootnode traversal process * @ param array $ btarr receives the array variable of the value, pass * @ return void */public function getPreorderTraversal ($ rootnode, & $ btarr) {if ($ rootnode! = Null) {$ btarr [] = $ rootnode-> mData; $ this-> getPreorderTraversal ($ rootnode-> mLchild, $ btarr ); $ this-> getPreorderTraversal ($ rootnode-> mRchild, $ btarr );}} /*** a non-recursive algorithm for first-order traversal ** @ param BTNode $ objRootNode binary tree root node * @ param array $ array variable of the value received by arrBTdata, pass * @ return void */public function getPreorderTraversalNoRecursion ($ objRootNode, & $ arrBTdata) {if ($ objRootNode instanceof BTNode) {$ objNode = $ objRootNode; $ objStack = new StackLinked (); do {$ arrBTdata [] = $ objNode-> mData; $ objRNode = $ objNode-> mRchild; if ($ objRNode! = Null) {$ objStack-> getPushStack ($ objRNode);} $ objNode = $ objNode-> mLchild; if ($ objNode = null) {$ objStack-> getPopStack ($ objNode) ;}} while ($ objNode! = Null);} else {$ arrBTdata = array ();}} /*** traverse a binary tree in ascending order ** @ param BTNode $ root node in the objRootNode process * @ param array $ array variable of the arrBTdata receiving value, pass * @ return void */public function getInorderTraversal ($ objRootNode, & $ arrBTdata) {if ($ objRootNode! = Null) {$ this-> getInorderTraversal ($ objRootNode-> mLchild, $ arrBTdata); $ arrBTdata [] = $ objRootNode-> mData; $ this-> getInorderTraversal ($ objRootNode-> mRchild, $ arrBTdata );}} /*** non-recursive algorithm for sequential traversal ** @ param BTNode $ objRootNode binary tree root node * @ param array $ array variable of the value received by arrBTdata, pass * @ return void */public function getInorderTraversalNoRecursion ($ objRootNode, & $ arrBTdata) {if ($ objRootNode instanceof BTNode) {$ objNode = $ objRootN Ode; $ objStack = new StackLinked (); // traverse the left subtree and access the root node do {while ($ objNode! = Null) {$ objStack-> getPushStack ($ objNode); $ objNode = $ objNode-> mLchild;} $ objStack-> getPopStack ($ objNode ); $ arrBTdata [] = $ objNode-> mData; $ objNode = $ objNode-> mRchild;} while (! $ ObjStack-> getIsEmpty (); // traverse the right subtree do {while ($ objNode! = Null) {$ objStack-> getPushStack ($ objNode); $ objNode = $ objNode-> mLchild;} $ objStack-> getPopStack ($ objNode ); $ arrBTdata [] = $ objNode-> mData; $ objNode = $ objNode-> mRchild;} while (! $ ObjStack-> getIsEmpty ();} else {$ arrBTdata = array ();}} /*** post-order traversal of a binary tree ** @ param BTNode $ root node during objRootNode traversal * @ param array $ array variable of the value received by arrBTdata, pass the * @ return void */public function getPostorderTraversal ($ objRootNode, & $ arrBTdata) {if ($ objRootNode! = Null) {$ this-> getPostorderTraversal ($ objRootNode-> mLchild, $ arrBTdata); $ this-> getPostorderTraversal ($ objRootNode-> mRchild, $ arrBTdata ); $ arrBTdata [] = $ objRootNode-> mData ;}/ *** post-order traversal of non-recursive algorithms * BTNode $ objRootNode binary tree root node array $ array variable of the arrBTdata receiving value, pass void */public function getPostorderTraversalNoRecursion ($ objRootNode, & $ arrBTdata) {if ($ objRootNode instanceof BTNode) {$ objNode = $ objRootNode; $ objStack = new Stack Linked (); $ objTagStack = new StackLinked (); $ tag = 1; do {while ($ objNode! = Null) {$ objStack-> getPushStack ($ objNode); $ objTagStack-> getPushStack (1); $ objNode = $ objNode-> mLchild ;} $ objTagStack-> getPopStack ($ tag); $ objTagStack-> getPushStack ($ tag); if ($ tag = 1) {$ objStack-> getPopStack ($ objNode ); $ objStack-> getPushStack ($ objNode); $ objNode = $ objNode-> mRchild; $ objTagStack-> getPopStack ($ tag); $ objTagStack-> getPushStack (2 );} else {$ objStack-> getPopStack ($ objNode); $ arrBTdata [] = $ objNode-> mData; $ ObjTagStack-> getPopStack ($ tag); $ objNode = null ;}} while (! $ ObjStack-> getIsEmpty ();} else {$ arrBTdata = array ();}} /*** traverse a binary tree hierarchically ** @ param BTNode $ objRootNode the root node of the binary tree * @ param array $ array variable of the value received by arrBTdata, pass the * @ return void */public function getLevelorderTraversal ($ objRootNode, & $ arrBTdata) {if ($ objRootNode instanceof BTNode) {$ objNode = $ objRootNode; $ objQueue = new QueueLinked (); $ objQueue-> getInsertElem ($ objNode); while (! $ ObjQueue-> getIsEmpty () {$ objQueue-> getDeleteElem ($ objNode); $ arrBTdata [] = $ objNode-> mData; if ($ objNode-> mLchild! = Null) {$ objQueue-> getInsertElem ($ objNode-> mLchild);} if ($ objNode-> mRchild! = Null) {$ objQueue-> getInsertElem ($ objNode-> mRchild) ;}} else {$ arrBTdata = array ();}} /*** calculate the number of leaf nodes of a binary tree ** @ param BTNode $ objRootNode root node * @ return int parameter transfer error return-1 **/public function getLeafNodeCount ($ objRootNode) {if ($ objRootNode instanceof BTNode) {$ intLeafNodeCount = 0; $ objNode = $ objRootNode; $ objStack = new StackLinked (); do {if ($ objNode-> mLchild = null & $ objNode-> mRchild = null) {$ intLeafNodeCount ++;} $ obj RNode = $ objNode-> mRchild; if ($ objRNode! = Null) {$ objStack-> getPushStack ($ objRNode);} $ objNode = $ objNode-> mLchild; if ($ objNode = null) {$ objStack-> getPopStack ($ objNode) ;}} while ($ objNode! = Null); return $ intLeafNodeCount;} else {return-1 ;}} /*** calculate the depth of a binary tree ** @ param BTNode $ objRootNode root node * @ return int parameter transfer error return-1 */public function getBinaryTreeDepth ($ objRootNode) {if ($ objRootNode instanceof BTNode) {$ objNode = $ objRootNode; $ objQueue = new QueueLinked (); $ queue = 0; $ objQueue-> getInsertElem ($ objNode ); $ objLevel = $ objNode; while (! $ ObjQueue-> getIsEmpty () {$ objQueue-> getDeleteElem ($ objNode); if ($ objNode-> mLchild! = Null) {$ objQueue-> getInsertElem ($ objNode-> mLchild);} if ($ objNode-> mRchild! = Null) {$ objQueue-> getInsertElem ($ objNode-> mRchild);} if ($ objLevel = $ objNode) {$ intBinaryTreeDepth ++; $ objLevel =@ $ objQueue-> mRear-> mElem;} return $ intBinaryTreeDepth;} else {return-1 ;}} echo"
"; $ Bt = new BinaryTree (array ('A', 'B', 'D','', '', 'e', 'e','', 'G ', '','', 'C', 'F', ''); echo" binary tree structure: \ r \ n "; var_dump ($ bt); $ btarr = array (); echo "first-order recursive traversal of binary trees: \ r \ n"; $ bt-> getPreorderTraversal ($ bt-> mRoot, $ btarr); var_dump ($ btarr); echo "first-order non-recursive traversal of binary trees: \ r \ n"; $ arrBTdata = array (); $ bt-> getPreorderTraversalNoRecursion ($ bt-> mRoot, $ arrBTdata); var_dump ($ arrBTdata); echo "sequential recursive traversal of binary trees: \ r \ n "; $ arrBTdata = array (); $ bt-> getInorderTraversal ($ bt-> mRoot, $ arrBTdata); var_dump ($ arrBTdata); echo "Ordinal Non-recursive traversal of a binary tree: \ r \ n "; $ arrBTdata = array (); $ bt-> getInorderTraversalNoRecursion ($ bt-> mRoot, $ arrBTdata); var_dump ($ arrBTdata ); echo "recursive binary tree traversal in descending order: \ r \ n"; $ arrBTdata = array (); $ bt-> getPostorderTraversal ($ bt-> mRoot, $ arrBTdata ); var_dump ($ arrBTdata); echo "post-order non-recursive traversal binary tree: \ r \ n"; $ arrBTdata = array (); $ bt-> getPostorderTraversalNoRecursion ($ bt-> mRoot, $ arrBTdata); var_dump ($ arrBTdata); echo "traverse binary trees by hierarchy: \ r \ n"; $ arrBTdata = array (); $ bt-> getLevelorderTraversal ($ bt-> mRoot, $ arrBTdata); var_dump ($ arrBTdata); echo "number of leaf nodes :". $ bt-> getLeafNodeCount ($ bt-> mRoot); echo "\ r \ n"; echo "binary tree depth :". $ bt-> getBinaryTreeDepth ($ bt-> mRoot); echo "\ r \ n"; echo :"; var_dump ($ bt-> getIsEmpty (); echo "leave the binary tree empty:"; $ bt-> setBinaryTreeNull (); var_dump ($ bt); echo"
";?>