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：递归求最长子树深度。可以参考姐妹题Leetcode 111. Minimum Depth of Binary Tree
代码：
1 /** 2 * Definition for a binary tree node. 3 * struct TreeNode { 4 * int val; 5 * TreeNode *left; 6 * TreeNode *right; 7 * TreeNode(int x) : val(x), left(NULL), right(NULL) {} 8 * }; 9 */ 10 class Solution { 11 public: 12 int maxDepth(TreeNode* root) { 13 if(!root){ 14 return 0; 15 } 16 int left=maxDepth(root->left),right=maxDepth(root->right); 17 return max(left,right)+1; 18 } 19 };
Leetcode 104. Maximum Depth of Binary Tree
原文：http://www.cnblogs.com/Deribs4/p/5655254.html