package com.guigu.tree;
/**
* @author: guorui fu
* @versiion: 1.0
* 二叉树 单向(当前节点无法找到父节点)
*/
public class BinaryTreeDemo {
public static void main(String[] args) {
//创建一颗二叉树
BinaryTree binaryTree = new BinaryTree();
HeroNode root = new HeroNode(1, "宋江");
HeroNode node2 = new HeroNode(2, "吴用");
HeroNode node3 = new HeroNode(3, "卢俊义");
HeroNode node4 = new HeroNode(4, "林冲");
HeroNode node5 = new HeroNode(5, "关胜");
root.setLeft(node2);
root.setRight(node3);
node3.setRight(node4);
node3.setLeft(node5);
binaryTree.setRoot(root);
//测试
// System.out.println("前序遍历=");//1,2,3,4
// binaryTree.preOrder();
// System.out.println("中序遍历=");//1,2,3,4
// binaryTree.infixOrder();
// System.out.println("后序遍历=");//1,2,3,4
// binaryTree.postOrder();
//前序查找
// System.out.println("前序查找");
// HeroNode resNode = binaryTree.preOrderSearch(5);
// if (resNode != null){
// System.out.println("信息为:" + resNode);
// }else{
// System.out.println("没有找到5的英雄");
// }
//中序查找
// System.out.println("中序查找");
// HeroNode resNode = binaryTree.infixOrderSearch(5);
// if (resNode != null){
// System.out.println("信息为:" + resNode);
// }else{
// System.out.println("没有找到5的英雄");
// }
//中序查找
// System.out.println("后序查找");
// HeroNode resNode = binaryTree.postOrderSearch(15);
// if (resNode != null){
// System.out.println("信息为:" + resNode);
// }else{
// System.out.println("没有找到5的英雄");
// }
//删除节点
System.out.println("删除前:");
binaryTree.preOrder();
binaryTree.delNode(5);
System.out.println("删除后:");
binaryTree.preOrder();
}
}
//定义二叉树
class BinaryTree{
private HeroNode root;
public void setRoot(HeroNode root) {
this.root = root;
}
//前序遍历
public void preOrder(){
if (this.root != null){
this.root.preOrder();
}else {
System.out.println("二叉树为null");
}
}
//中序遍历
public void infixOrder(){
if (this.root != null){
this.root.infixOrder();
}else {
System.out.println("二叉树为null");
}
}
//后序遍历
public void postOrder(){
if (this.root != null){
this.root.postOrder();
}else {
System.out.println("二叉树为null");
}
}
//前序查找
public HeroNode preOrderSearch(int no){
if (root != null){
return root.preOrderSearch(no);
}else {
return null;
}
}
//中序查找
public HeroNode infixOrderSearch(int no){
if (root != null){
return root.infixOrderSearch(no);
}else {
return null;
}
}
//后序查找
public HeroNode postOrderSearch(int no){
if (root != null){
return root.postOrderSearch(no);
}else {
return null;
}
}
//删除节点 直接删除节点与及其左右节点
public void delNode(int no){
if (root != null){//root是否为null
if (root.getNo() == no){//root是否为删除对象
root = null;
}else {
//判断子节点
root.delNode(no);
}
}else {
System.out.println("无节点可删除");
}
}
}
//创建heroNode节点
class HeroNode {
private int no ;
private String name;
private HeroNode left;//默认null
private HeroNode right;//默认null
public HeroNode(int no, String name) {
this.no = no;
this.name = name;
}
public int getNo() {
return no;
}
public void setId(int no) {
this.no = no;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public HeroNode getLeft() {
return left;
}
public void setLeft(HeroNode left) {
this.left = left;
}
public HeroNode getRight() {
return right;
}
public void setRight(HeroNode right) {
this.right = right;
}
@Override
public String toString() {
return "HeroNode{" +
"no=" + no +
", name='" + name + '\'' +
'}';
}
//前序遍历
public void preOrder(){
System.out.println(this);//先输出父节点
//递归左子树
if (this.left != null){
this.left.preOrder();
}
//递归右子树
if (this.right != null){
this.right.preOrder();
}
}
//中序遍历
public void infixOrder(){
//递归左子树
if (this.left != null){
this.left.infixOrder();
}
System.out.println(this);//输出父节点
//递归右子树
if (this.right != null){
this.right.infixOrder();
}
}
//后序遍历
public void postOrder(){
//递归左子树
if (this.left != null){
this.left.postOrder();
}
//递归右子树
if (this.right != null){
this.right.postOrder();
}
System.out.println(this);//输出父节点
}
//前序遍历查找
public HeroNode preOrderSearch(int no){//查找编号
//比较当前节点是不是
if (this.no == no){
return this;
}
//查看左节点 找到后返回给resNode
HeroNode resNode = null;
if (this.left != null){
resNode = this.left.preOrderSearch(no);
}
//中间加return,左子树找到 这时就不用再去执行下面的右子树
if (resNode != null){
return resNode;
}
if (this.right != null){
resNode = this.right.preOrderSearch(no);
}
return resNode;
}
//中序遍历查找
public HeroNode infixOrderSearch(int no){
//判断当前左节点是否为null,不为null则递归中序查找
HeroNode resNode = null;
if (this.left != null){//向左查找
resNode = this.left.infixOrderSearch(no);//递归查找
}
if (resNode != null){
return resNode;
}
//查找时判断no是否相等
if (this.no == no){
return this;
}
//否则进行右序查找
if (this.right != null){
resNode = this.right.infixOrderSearch(no);
}
return resNode;
}
//后序查找
public HeroNode postOrderSearch(int no){
HeroNode resNode = null;
if (this.left != null){
resNode = this.left.postOrderSearch(no);
}
if (resNode != null){
return resNode;
}
if (this.right != null){
resNode = this.right.postOrderSearch(no);
}
if (resNode != null){
return resNode;
}
if (this.no == no){
return this;
}
return resNode;
}
//递归删除节点
public void delNode(int no){
if (this.left != null && this.left.no == no){//左子节点是删除对象
//左子节点的左子节点不为null
if (this.left.left != null){
if (this.left.right !=null){
this.left.left = this.left.right;
}
this.left = this.left.left;
}
return;
}
if (this.right != null && this.right.no == no){
this.right = null;
return;
}
//左子树递归
if (this.left != null){
this.left.delNode(no);
}
//右子树递归
if (this.right != null) {
this.right.delNode(no);
}
}
}