# maxnum depth of binary tree

## maxnum depth of binary tree

### The most simple one

```
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) {
13 return !root ? 0:max(maxDepth(root->left),maxDepth(root->right))+1;
14 }
15 };
```