Java Data Structure-Binary Tree

1. implement various traversal of Binary Trees

Package COM. jzm. stackqueuetree; public class bintree {private final static int max = 50; private object data; private bintree left, right; bintree [] elements = new bintree [Max]; int front; int rear; Public bintree () {} public bintree (Object Data) {This. data = data; left = right = NULL;} public bintree (Object Data, bintree left, bintree right) {This. data = data; this. left = left; this. right = right ;} @ Overridepublic string tostring () {return data. tostring ();} // traverse public static void preorder (bintree parent) {If (parent = NULL) {return;} System in the forward order. out. print (parent. data + ""); preorder (parent. left); preorder (parent. right);} // traverse public static void inorder (bintree parent) {If (parent = NULL) {return;} inorder (parent. left); system. out. print (parent. data + ""); inorder (parent. right );}// Traverse public static void postorder (bintree parent) {If (parent = NULL) {return;} postorder (parent. left); postorder (parent. right); system. out. print (parent. data + "") ;}// traverse public void layerorder (bintree parent) {elements [0] = parent; front = 0; Rear = 1; while (front <rear) {try {If (elements [Front]. data! = NULL) {system. Out. Print (elements [Front]. Data + ""); If (elements [Front]. Left! = NULL) elements [rear ++] = elements [Front]. Left; If (elements [Front]. Right! = NULL) elements [rear ++] = elements [Front]. right; front ++;} // end if} catch (exception e) {break ;}// end while} // calculates the height of the Public int height () tree () {int Height = 0; If (this = NULL) {return-1;} int leftheimpaired = (Left = NULL )? 0: Left. Height (); int rightheimpaired = (Right = NULL )? 0: Right. Height (); Height = leftheimpaired <rightheimpaired? Rightheimpaired: leftheimpaired; return height + 1;} // if the object is not in the tree,-1 is returned; otherwise, the hierarchy of the object in the tree is returned, specify the root node as the first public int level (Object object) {int leveltree = 0; If (this = NULL) {return-1 ;} // specify the root node as the first layer if (object. equals (data) {return 1;} int leftlevel = (Left = NULL )? -1: Left. Level (object); int rightlevel = (Right = NULL )? -1: Right. Level (object); If (leftlevel <0 & rightlevel <0) {return-1;} leveltree = (leftlevel <rightlevel )? Rightlevel: leftlevel; return leveltree + 1;} // change the child of each node in the tree to the public void reflect () {If (this = NULL) return; If (left! = NULL) {left. Reflect ();} If (right! = NULL) {right. reflect ();} bintree temp = left; left = right; Right = temp;} // remove all nodes in the tree and output the removed node public void defoliate () {string innernode = ""; if (this = NULL) return; // if it is a leaf node, remove if (Left = NULL & Right = NULL) {system. out. print (This + ""); Data = NULL; return;} // remove the left subtree if (left! = NULL) {left. defoliate (); left = NULL;} innernode + = This + ""; Data = NULL; // remove the right subtree if (right! = NULL) {right. defoliate (); Right = NULL ;}} public static void main (string [] ARGs) {bintree E = new bintree ("e "); bintree G = new bintree ("G"); bintree H = new bintree ("H"); bintree I = new bintree ("I "); bintree d = new bintree ("D", null, g); bintree F = new bintree ("F", H, I); bintree B = new bintree ("B ", d, e); bintree c = new bintree ("C", F, null); bintree tree = new bintree ("A", B, c); system. out. println ("heigh =" + tree. height (); system. out. println ("preordered Result:"); tree. preorder (tree); system. out. println (""); system. out. println ("intermediate result:"); tree. inorder (tree); system. out. println (""); system. out. println ("result in descending order:"); tree. postorder (tree); system. out. println (""); system. out. println ("layered traversal result:"); tree. layerorder (tree); system. out. println (""); system. out. println ("level (d)" + tree. level ("B "));}}