MaximumDepthOfBinaryTree104.java

/**
 * 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; }
 * }
 */


import java.util.Stack;


public class MaximumDepthOfBinaryTree104 {
    public int maxDepth(TreeNode root) {
       if (root == null){
           return 0;
       }

       int left = maxDepth(root.left);
       int right = maxDepth(root.right);
       return Math.max(left, right) + 1;
   }

}