Confluent Interview Experience For SDE (On-Campus)

Initial Shortlist:

College: IIT Jodhpur

Location: Remote

Open to all branches

CGPA: 7

Round 0: Coding Round OA

The first round consisted of three coding questions. I successfully solved one question and partially solved the other two. Alongside 13 other students (all from CSE, AI, and EE), I advanced to the interview stage.

Round 1: Time 45 minutes

In this round, lasting 45 minutes, I faced a single DSA question – Leetcode hard: “Number of Atoms” (Leetcode Problem Link). I successfully solved the question, ran all dry-run test cases, and discussed my approach with the interviewer, who provided valuable suggestions for improvement.

Round 2: Time 1 hour

Following the initial round, eight students proceeded to the second round. This stage began with a general introduction, followed by the implementation of a thread-safe LRU cache. I proposed a solution involving three functions: put (to add an element), get (to access an element), and size (to determine the cache size). I emphasized that no two functions could be accessed simultaneously by different threads. Initially, I suggested using a “turn” variable to manage thread access. However, the interviewer pointed out a flaw regarding multiple accesses to the size function, leading to my revised solution involving two variables, “turn” and “turn_size.” The interviewer presented a potential issue with thread starvation during size function access by numerous threads, prompting my solution to incorporate a semaphore. Additionally, I discussed the Reader-Writer problem and its various solutions. For a detailed solution, refer to Thread Safe LRU Cache.

Round 3: HR Round

Post the second round, only two students, including myself, progressed to the HR round. This stage involved general questions about strengths, weaknesses, something to be proud of, and something not to be proud of, etc.

Result: Only one student secured the role, and I was placed on the waitlist.