PHP cash balance binary tree (AVL tree)

PHP implements a balanced binary tree (AVL tree) & lt ;? PhprequirebstOrder. php; $ testrange (); $ testarray (,); $ treenewBst ($ test, true); $ tree-& gt; deleteN PHP implements a balanced binary tree (AVL tree)

 DeleteNode ('30'); (the non-balance tree can be deleted, and the balance tree does not have a write delete operation) print_r ($ tree-> getTree ();?>

BstOrder. php

 Data = $ data; $ this-> left = $ left; $ this-> right = $ right; $ this-> bf = $ bf;} public function getBf () {return $ this-> bf;} public function setBf ($ bf) {$ this-> bf = $ bf;} public function getData () {return $ this-> data;} public function setData ($ data) {$ this-> data = $ data;} public function & getLeft () {return $ this-> left;} public function & getRight () {return $ this-> right;} public function setLeft ($ l Eft) {$ this-> left = $ left;} public function setRight ($ right) {$ this-> right = $ right ;}} class Bst {private $ head; // header node private $ data; // The initial input data, in the form of an array, such as array ('A', 'B'); private $ tag; // the previous node set during search (invalid, useless) // $ bst: whether to create AVL tree public function Bst ($ data, $ bst = FALSE) {$ this-> data = $ data; $ this-> head = NULL; if (! $ Bst) {$ this-> createBst ();} else {$ this-> createBfBst () ;}} public function createBfBst () {foreach ($ this-> data as $ value) {$ this-> insertBfNode ($ this-> head, $ value) ;}} private function insertBfNode (& $ node, $ value) {if ($ node = NULL) {$ node = new Node ($ value, 0); return TRUE ;} else {if ($ node-> getData ()> $ value) {if (! $ This-> insertBfNode ($ node-> getLeft (), $ value) {return FALSE;} switch ($ node-> getBf () {case 0: $ node-> setBf (1); return TRUE; case 1: $ this-> rightRotate ($ node); return FALSE; case-1: $ node-> setBf (0); return FALSE ;}} elseif ($ node-> getData () <$ value) {if (! $ This-> insertBfNode ($ node-> getRight (), $ value) {return FALSE;} switch ($ node-> getBf () {case 0: $ node-> setBf (-1); return TRUE; case 1: $ node-> setBf (0); return FALSE; case-1: $ this-> leftRotate ($ node); return FALSE ;}} else {return FAlse ;}} private function excuteLeft (& $ node) {$ temp = $ node; $ node = $ node-> getRight (); $ temp-> setRight ($ node-> getLeft (); $ node-> setLeft ($ temp);} private function ExcuteRight (& $ node) {$ temp = $ node; $ node = $ node-> getLeft (); $ temp-> setLeft ($ node-> getRight ()); $ node-> setRight ($ temp);} private function leftRotate (& $ node) {$ right = & $ node-> getRight (); switch ($ right-> getBf () {case 1: $ left = & $ right-> getLeft (); switch ($ left-> getBf ()) {case-1: $ right-> setBf (0); $ node-> setBf (1); break; case 0: $ right-> setBf (0 ); $ node-> setBf (0); break; case 1: $ right-> setBf (-1); $ Node-> setBf (0); break;} $ left-> setBf (0); $ this-> excuteRight ($ right ); $ this-> excuteLeft ($ node); break; case-1: $ node-> setBf (0); $ right-> setBf (0 ); $ this-> excuteLeft ($ node); break;} private function rightRotate (& $ node) {$ left = & $ node-> getLeft (); switch ($ left-> getBf () {case-1: $ right = & $ left-> getRight (); switch ($ right-> getBf ()) {case-1: $ left-> setBf (1); $ node-> setBf (0); break; case 0: $ le Ft-> setBf (0); $ node-> setBf (0); break; case 1: $ left-> setBf (0 ); $ node-> setBf (-1); break;} $ right-> setBf (0); $ this-> excuteLeft ($ left ); $ this-> excuteRight ($ node); break; case 1: $ node-> setBf (0); $ left-> setBf (0 ); $ this-> excuteRight ($ node); break ;}} public function createBst () {foreach ($ this-> data as $ value) {$ this-> insertNode ($ value) ;}// $ pre: whether to return the public function & searchBst (& $ node, $ Key, $ pre = FALSE) {if ($ node = NULL) {if ($ pre) {return $ this-> tag;} else {return FALSE ;}} if ($ key> $ node-> getData () {$ this-> tag = $ node; return $ this-> searchBst ($ node-> getRight (), $ key, $ pre);} elseif ($ key <$ node-> getData () {$ this-> tag = $ node; return $ this-> searchBst ($ node-> getLeft (), $ key, $ pre);} else {return $ node ;}} public function insertNode ($ key) {if (! $ This-> head) {$ this-> head = new Node ($ key);} else {$ pre = $ this-> searchBst ($ this-> head, $ key, TRUE); $ node = new Node ($ key); if ($ pre-> getData ()> $ key) {$ pre-> setLeft ($ node);} else {$ pre-> setRight ($ node) ;}} public function deleteNode ($ key) {$ node = & $ this-> searchBst ($ this-> head, $ key); if (! $ Node) {return FALSE;} if ($ node-> getLeft () = NULL) {$ node = $ node-> getRight ();} elseif ($ node-> getRight () = NULL) {$ node = $ node-> getLeft ();} else {$ leftBig = & $ this-> searchLeftBig ($ node); $ node-> setData ($ leftBig-> getData ()); if ($ leftBig-> getLeft () {$ leftBig = $ leftBig-> getLeft () ;}} private function & searchLeftBig (& $ key) {$ result = & $ key-> getLeft (); while ($ result) {if ($ result-> getRight () = NULL) {return $ result ;}$ result = & $ result-> getRight () ;}} public function getTree () {return $ this-> head ;}}?>