java 二叉树

package erchashu;import java.util.Scanner;class CBTType{String data;CBTType left;CBTType right;}public class BinaryTree{static final int MAXLEN = 20;static Scanner input = new Scanner(System.in);@SuppressWarnings("unused")CBTType InitTree(){CBTType rootNode;if((rootNode = new CBTType())!=null){System.out.print("input the rootNode data:\n");rootNode.data = input.next();rootNode.left = null;rootNode.right = null;if(rootNode!=null)return rootNode;elsereturn null;}return null;}void AddTreeNode(CBTType rootNode){CBTType treeNode,parent;String data;int menusel;if((treeNode = new CBTType())!=null){System.out.print("input the treeNode data:\n");treeNode.data = input.next();treeNode.left = null;treeNode.right = null;System.out.print("input the parent data of treeNode:\n");data = input.next();parent = TreeFindNode(rootNode,data);if(parent == null){System.out.print("can not find the parent node:\n");System.out.printf("the binary tree test end!");treeNode = null;System.exit(0);}System.out.print("1.add treeNode as left-son-tree node;2.add treeNode as right-son-tree node:\n");do{menusel = input.nextInt();switch(menusel){case 1:if(parent.left != null)System.out.print("the left-son-tree node is not empty!\n");elseparent.left = treeNode;break;case 2:if(parent.right != null)System.out.print("the right-son-tree node is not empty!\n");elseparent.right = treeNode;break;default:System.out.print("invalid parameter!\n");}}while(menusel!=1 && menusel!=2);}}CBTType TreeFindNode(CBTType rootNode,String data){CBTType treeNode;if(rootNode == null)return null;else{if(rootNode.data.equals(data))return rootNode;else{if((treeNode=TreeFindNode(rootNode.left,data)) != null)return treeNode;else if((treeNode=TreeFindNode(rootNode.right,data)) != null)return treeNode;elsereturn null;}}}CBTType TreeLeftNode(CBTType treeNode){if(treeNode != null)return treeNode.left;elsereturn null;}CBTType TreeRightNode(CBTType treeNode){if(treeNode != null)return treeNode.right;elsereturn null;}int TreeIsEmpty(CBTType rootNode){if(rootNode != null)return 1;elsereturn 0;}int TreeDepth(CBTType rootNode){int depthLeft,depthRight;if(rootNode == null)return 0;else{depthLeft = TreeDepth(rootNode.left);depthRight = TreeDepth(rootNode.right);if(depthLeft > depthRight)return (depthLeft + 1);elsereturn (depthRight + 1);}}void ClearTree(CBTType rootNode){if(rootNode != null){ClearTree(rootNode.left);ClearTree(rootNode.right);rootNode = null;}}void TreeNodeData(CBTType treeNode){System.out.printf("%s",treeNode.data);System.out.printf("\t");}void LevelTree(CBTType rootNode){CBTType p;CBTType[]q = new CBTType[MAXLEN];int head = 0;int tail = 0;if(rootNode != null){tail = (tail+1)%MAXLEN;q[tail] = rootNode;}while(head != tail){head = (head+1)%MAXLEN;p = q[head];TreeNodeData(p);if(p.left != null){tail = (tail+1)%MAXLEN;q[tail] = p.left;}if(p.right != null){tail = (tail+1)%MAXLEN;q[tail] = p.right;}}}void DLRTree(CBTType rootNode){if(rootNode != null){TreeNodeData(rootNode);DLRTree(rootNode.left);DLRTree(rootNode.right);}}void LDRTree(CBTType rootNode){if(rootNode != null){LDRTree(rootNode.left);TreeNodeData(rootNode);LDRTree(rootNode.right);}}void LRDTree(CBTType rootNode){if(rootNode != null){LRDTree(rootNode.left);LRDTree(rootNode.right);TreeNodeData(rootNode);}}public static void main(String[] args){CBTType rootNode = null;int menusel;BinaryTree tree = new BinaryTree();rootNode = tree.InitTree();do{System.out.print("select menu to add treeNode:\n");System.out.printf("0.exit\t");System.out.printf("1.add treeNode\n");menusel = input.nextInt();switch(menusel){case 1:tree.AddTreeNode(rootNode);break;case 2:break;default:;}}while(menusel != 0);do{System.out.print("select menu to traverse binary tree,0 represent to exit:\n");System.out.print("1.traverse by DLR\t");System.out.print("2.traverse by LDR\t");System.out.print("3.traverse by LRD\t");System.out.print("4.traverse by level\n");menusel = input.nextInt();switch(menusel){case 0:break;case 1:System.out.print("the result of traversing by DLR:");tree.DLRTree(rootNode);System.out.print("\n");break;case 2:System.out.print("the result of traversing by LDR:");tree.LDRTree(rootNode);System.out.print("\n");break;case 3:System.out.print("the result of traversing by LRD:");tree.LRDTree(rootNode);System.out.print("\n");break;case 4:System.out.print("the result of traversing by level:");tree.LevelTree(rootNode);System.out.print("\n");break;default:;}}while(menusel != 0);System.out.printf("the depth of the binary tree is:%d\n",tree.TreeDepth(rootNode));tree.ClearTree(rootNode);rootNode = null;System.out.printf("the binary tree test end!");}}