rotation on Binary Tree
Last updated: October 19, 2025
Quick Overview
Given a binary tree, implement a function to perform a rotation operation on the tree at a specified node. The rotation should either be a left or right rotation, depending on the input parameter, and the function should return the new root of the modified tree. Ensure that your solution handles edge cases, such as rotations on leaf nodes and empty trees.
Discord
October 19, 20253
7
3,704 solved
Given a binary tree, implement a function to perform a rotation operation on the tree at a specified node. The rotation should either be a left or right rotation, depending on the input parameter, and the function should return the new root of the modified tree. Ensure that your solution handles edge cases, such as rotations on leaf nodes and empty trees.
Discord uses this problem in the Phone Screen to evaluate your algorithmic thinking. They expect you to discuss multiple approaches, analyze trade-offs between them, and implement the optimal solution with clean, readable code.
What the Interviewer Expects
- Quickly identify the optimal approach and its theoretical basis
- Handle complex algorithm design with multiple interacting components
- Write concise, elegant code under time pressure
- Prove correctness of your approach and discuss alternative solutions
- Optimize beyond the obvious: discuss constant factor improvements
- Address follow-up variations and explain how the solution generalizes
Key Topics to Cover
How to Approach This
- Clarify input constraints and edge cases before writing code.
- Walk through your approach verbally and confirm with the interviewer before coding.
- Start with a brute force solution, then optimize. Mention time and space complexity.
- Test your solution with examples, including edge cases like empty input or duplicates.
- Consider common patterns: sliding window, two pointers, hash map, BFS/DFS, dynamic programming.
Possible Follow-up Questions
- How would you modify your solution to handle streaming input?
- Can you optimize the space complexity of your solution?
- How would you test this solution thoroughly?
- What if the input doesn't fit in memory?
Sharpen Your Skills on Codemia
Practice similar problems with our interactive workspace, get AI feedback, and track your progress.
Practice DSA ProblemsSample Answer
Problem Analysis
To perform a rotation on a binary tree at a specified node, we need to recognize that this problem can be efficiently solved using the concept of tree rotations, which are essentially local operations...
Approach
- Find the Node: We will first locate the node at which the rotation will occur. This can be done using a recursive traversal of the tree. If the specified node is not found, we will return the o...
Submit Your Answer
