EasyTreesAI interview only
Maximum Depth of Binary Tree
Asked atamazongooglelinkedinappleyahoo
01 · Problem
Given the root of a binary tree, return its maximum depth.
A binary tree's maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.
02 · Examples
Example 01
3
/ \
9 20
/ \
15 7Input
root = [3,9,20,null,null,15,7]
Output
3
The tree has 3 levels. The longest path is 3 -> 20 -> 15 (or 3 -> 20 -> 7), which has 3 nodes.
Example 02
1
\
2Input
root = [1,null,2]
Output
2
The tree has 2 levels. The root is 1, and its right child is 2. The longest path has 2 nodes.
03 · Constraints
- 01The number of nodes in the tree is in the range [0, 104].
- 02-100 <= Node.val <= 100
04 · Optimal complexity
- Time
- O(n)
- Space
- O(h)
05 · Two ways to work on it
Practice it alone or rehearse it as an interview.
Practice Mode gives you an editor and test runs, nothing else. AI Interview Mode puts a voice interviewer on the other side, adds a clock, and ends with a scored summary of the round.