leetcode 104: Maximum Depth of Binary Tree

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */
public class Solution {
    public int maxDepth(TreeNode root) {
        if(root == null) 
            return 0;
        else {
            int lDepth = maxDepth(root.left);
            int rDepth = maxDepth(root.right);
            return lDepth > rDepth ? lDepth+1 : rDepth +1;
        }
    }
}