LeetCode Maximum Depth of Binary Tree

Description

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.

The original problem is here.

The original code is here.

My Solution

I solve this problem in C++, as below:

/*
*Maximum Depth of Binary Tree
*Author: shuaijiang
*Email: zhaoshuaijiang8@gmail.com
*/
#include<iostream>
#include<math.h>
#include<stdlib.h>
using namespace std;

/**
 * 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==NULL)
            return 0;
        if(root->left!=NULL && root->right==NULL)
            return 1+maxDepth(root->left);
        if(root->left==NULL && root->right!=NULL)
            return 1+maxDepth(root->right);
        return max(1+maxDepth(root->left),1+maxDepth(root->right));
    }
};

Note

In the solution, recursion is needed.