leetcode 104
一个简单的递归,回朔时候可以求出从各个叶子到当前根的最大长度.
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==NULL)return 0; 14 int a=maxDepth(root->left)+1; 15 int b=maxDepth(root->right)+1; 16 return a>b?a:b; 17 } 18 };