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文章目录
  1. 1. Maximum Depth of Binary Tree
    1. 1.1. 题目
    2. 1.2. 思路
    3. 1.3. 解题

Maximum Depth of Binary Tree

题目

Given a binary tree, find its maximum depth.

The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.

思路

max(左分支高度,右分支高度)+1
队列，BFS

解题

c++版

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/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */
class Solution {
public:
    int maxDepth(TreeNode* root) {
        if(!root)
            return 0;
        return 1+max(maxDepth(root->left),maxDepth(root->right));
    }
};

Python版

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# Definition for a  binary tree node
# class TreeNode:
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None

class Solution:
    # @param root, a tree node
    # @return an integer
    def maxDepth(self, root):
        Depth=0
        if not root:
            return 0
        queue=[]
        queue.append(root)
        count=len(queue)
        while len(queue)!=0:
            tmp=queue[0]
            del queue[0]
            count=count-1
            if tmp.left:
                queue.append(tmp.left)
            if tmp.right:
                queue.append(tmp.right)
            if count==0:
                Depth+=1
                count=len(queue)
        return Depth

leetcode
leetcode,tree
文章目录
  1. 1. Maximum Depth of Binary Tree
    1. 1.1. 题目
    2. 1.2. 思路
    3. 1.3. 解题