# Maximum Depth of Binary Tree

In this article, I explain about how to find the Maximum Depth of Binary Tree which is also called as Height 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.

Note: A leaf is a node with no children.

Example:

Given binary tree `[3,9,20,null,null,15,7]`,

```    3
/ \
9  20
/  \
15   7```

return its depth = 3.

## Solution

```/**
* Definition for a binary tree node.
* public class TreeNode {
*     public int val;
*     public TreeNode left;
*     public TreeNode right;
*     public TreeNode(int x) { val = x; }
* }
*/
public class Solution {
int h = 0;
public int MaxDepth(TreeNode root) {

if(root == null)
return 0;
int leftSubTreeHeight = MaxDepth(root.left);
int rightSubTreeHeight = MaxDepth(root.right);

if(leftSubTreeHeight > rightSubTreeHeight)
h = 1 + leftSubTreeHeight;
else
h = 1 + rightSubTreeHeight;

return h;
}
}
```