Maximum Depth of a 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.

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */
public class MaximumDepthOfABinaryTree {
    public int maxDepth(TreeNode root) {
        if(root == null) {
            return 0;
        }
       
        return 1 + Math.max(maxDepth(root.left), maxDepth(root.right));
    }
}