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.

我想不用多說了吧
code也很簡單...

   class Solution {  
    public:  
        int maxDepth(TreeNode *root) {  
 
            if(root == NULL)
            {
                return 0;
            }
            
            return 1 + max( maxDepth(root->left), maxDepth(root->right) );  
        }  
    };  

搞定