二叉树遍历

package com.lkr.shujujiegou;

/**
 * @AUTHOR:LKR
 * @DATE:2019/3/18
 * @DESCRIPTION:二叉树
 **/
public class BinaryTree {
    private Node root;
    public BinaryTree(){
        root = null;
    }
    //将data插入到排序二叉树中
    public void insert(int data){
        Node newNode = new Node(data);
        if(root == null){
            root = newNode;
        }
        else {
            Node currennt = root;
            Node parent;
            while (true)//寻找插入的位置
            {
                parent = currennt;
                if(data<currennt.data){
                    currennt = currennt.left;
                    if(currennt == null){
                        parent.left = newNode;
                        return;
                    }
                }else {
                    currennt = currennt.right;
                    if(currennt == null){
                        parent.right = newNode;
                        return;
                    }
                }
            }
        }
    }
    //将数值输入构建二叉树
    public void buildTree(int [] data){
        for (int i = 0;i<data.length;i++){
            insert(data[i]);
        }
    }
    //中序遍历方法递归实现
    public void inOrder(Node localNode){
        if(localNode != null){
            inOrder(localNode.left);
            System.out.print(localNode.data+" ");
            inOrder(localNode.right);
        }
    }
    public void inOrder(){
        this.inOrder(this.root);
    }
    //先序遍历方法递归实现
    public void preOrder(Node localNode) {
        if (localNode != null) {
            System.out.print(localNode.data + " ");
            preOrder(localNode.left);
            preOrder(localNode.right);
        }
    }
    public void preOrder(){
        this.preOrder(this.root);
    }
    //后序遍历方法递归实现
    public void postOrder(Node localNode){
        if(localNode != null){
            preOrder(localNode.left);
            preOrder(localNode.right);
            System.out.print(localNode.data+" ");
        }
    }
    public void postOrder(){
        this.preOrder(this.root);
    }

    //测试
    public static void main(String[] args) {
        BinaryTree binaryTree = new BinaryTree();
        int[] data = {2,4,5,8,9,44,1,7,23,6};
        binaryTree.buildTree(data);
        System.out.println("先序遍历结果：");
        binaryTree.preOrder();
        System.out.println();
        System.out.println("中序遍历结果：");
        binaryTree.inOrder();
        System.out.println();
        System.out.println("后序遍历结果：");
        binaryTree.postOrder();
        System.out.println();


    }
}