Round 1: OA
Questions: Basic 2-hour HackerRank challenge. Two questions based on heap and DFS.
- 1 Easy
- 1 Medium
Passed all test cases.
Candidate's Approach
No approach provided.
Interviewer's Feedback
No feedback provided.
Round 2: DSA
Questions:
- Given a tree, multiply the value in each node with its inverted level order and return the sum of all these values.
- Given a dependency graph like (A -> B -> C), print an order of execution such that all dependency items are executed first before the target items. Graph can have a cycle, and in case of a cycle throw an error.
Candidate's Approach
- For the first question, suggested a basic DFS approach where each element of the same level is stored in an array. Later optimized by storing the sum of each level directly and multiplying them with their reverse levels.
- For the second question, implemented a straightforward DFS approach with cycle detection.
Interviewer's Feedback
Interviewer seemed satisfied with both answers.
Round 3: Debugging and System Design
Questions:
- Debugging: Check if a linked list is a palindrome (pseudo-code provided).
- System Design: Design a system where many users request some X data.
Candidate's Approach
- Debugging: Successfully pointed out logical errors in the provided pseudo-code and dry-ran a few test cases.
- System Design: Started with a basic API server, load balancer, and database. Suggested horizontal scaling for each component, database partitioning, replication, and caching strategies like LRU and LFU. Discussed integrated cache with the DB query engine and strategies like cache-aside and read-through.
Interviewer's Feedback
Interviewer seemed satisfied with the performance in this round, and there were still 10 minutes left for discussion.