Maximum Depth of Binary Tree

• LintCode: No.97-Maximum Depth of Binary Tree Height
• Problem:

  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.
  

• Example:

  Given a binary tree as follow:
      1  
     / \  
    2   3  
   / \  
  4   5  
  The maximum depth is 3.
  

• Analysis:

  Visited every nodes and got max depth recursively.
  

• Java:

  • Recursive:

    public class Solution {
        public int maxDepth(TreeNode root) {
        // write your code here
            if (root == null) {
                return 0;
            }
            return 1 + Math.max(maxDepth(root.left), maxDepth(root.right));
        }
    }
    

• Time Complexity:

  • O(n), n is the number of nodes