Maximum Depth of Binary Tree

 1 /**
 2  * Definition for binary tree
 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, int dep = 0) {
13         if(root==NULL)
14             return dep;
15         int ldep = maxDepth(root->left,dep+1);
16         int rdep = maxDepth(root->right,dep+1);
17         return max(ldep,rdep);
18     }
19 };