97 · Maximum Depth of Binary Tree - LintCode

# Description

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.

The answer will not exceed 5000

# Example

Example 1:

Input:

tree = {}

Output:

Explanation:

The height of empty tree is 0.

Example 2:

Input:

tree = {1,2,3,#,#,4,5}

Output:

Explanation:

Like this:
1
/ \
2 3
/ \
4 5
it will be serialized

	/**
	* Definition of TreeNode:
	* public class TreeNode {
	* public int val;
	* public TreeNode left, right;
	* public TreeNode(int val) {
	* this.val = val;
	* this.left = this.right = null;
	* }
	* }
	*/

	public class Solution {
	/**
	* @param root: The root of binary tree.
	* @return: An integer
	*/
	public int maxDepth(TreeNode root) {
	if (root == null) {
	return 0;
	}

	int leftMax = maxDepth(root.left);
	int rightMax = maxDepth(root.right);

	return Math.max(leftMax, rightMax) + 1;
	}
	}