package com.cpucode.java.simple;

import java.util.LinkedList;

import java.util.Queue;

/**

* 题目描述

* 输入一棵二叉树，求该树的深度。从根结点到叶结点依次经过的结点（含根、叶结点）形成树的一条路径，最长路径的长度为树的深度。

* 示例1

* 输入

* {1,2,3,4,5,#,6,#,#,7}

* 返回值

* 4

*

* @author : cpucode

* @Date : 2021/1/23

* @Time : 11:52

* @Github : https://github.com/CPU-Code

* @CSDN : https://blog.csdn.net/qq_44226094

*/

public class Jz38 {

public class TreeNode {

int val = 0;

TreeNode left = null;

TreeNode right = null;

public TreeNode(int val) {

this.val = val;

}

}

public int TreeDepth(TreeNode root) {

if(root == null){

return 0;

}

Queue<TreeNode> q = new LinkedList<TreeNode>();

q.add(root);

//深度

int depth = 0;

//当前遍历的数

int count = 0;

//当层遍历的总数

int nextcount = q.size();

while(q.size() > 0){

TreeNode node = q.poll();

if(node.left != null){

q.add(node.left);

}

if(node.right != null){

q.add(node.right);

}

count++;

if(count == nextcount){

depth++;

count = 0;

nextcount = q.size();

}

}

return depth;

}

}