104. Maximum Depth of Binary Tree

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.

题意：求二叉树的树高。

思路：递归求解。

/** * 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;else{int left, right;left = maxDepth(root->left) + 1;right = maxDepth(root->right) + 1;return left > right ? left : right;}}};