Maximum Depth of Binary Tree——Difficulty：Easy

Problem :

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.

Example:

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Algorithm:

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水题水一下。。。

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Code：

/** * 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;        return max(maxDepth(root->left)+1,maxDepth(root->right)+1);    }};