Hotstar | SDE2 | Remote/India | July 2024 [Reject]
Summary
I interviewed for an SDE2 position at Hotstar in July 2024. The interview process spanned four rounds covering exploratory discussion, data structures & algorithms, system design, and infrastructure. Despite performing well in most technical rounds, I was ultimately rejected.
Full Experience
I recently interviewed for the SDE2 role at Hotstar. I have 2.3 years of experience as a fullstack software developer at a product-based MNC. The interview process was quite extensive, lasting over a month, and consisted of four main rounds.
Round 1: Exploratory Discussion (1 hour)
This round began with a discussion about my past experiences and the SDLC practices followed at my current company. We also had high-level design discussions. Towards the end, I was given an easy coding problem to solve: to check if a string exists in a circular string.Round 2: Data Structures & Algorithms (1 hour)
In this round, I was presented with two DSA problems. The first was the classic Climbing Stairs problem. The second problem asked me to determine if a given Sudoku board with some empty spots was valid. I successfully answered both problems.Round 3: Design (1 hour)
This round kicked off with an architecture discussion of my current project. Following that, we delved into a system design problem: 'Design a URL shortener'. I discussed various aspects including Back of the Envelope estimations, API contracts, database design, and high-level strategies for efficiently generating random unique short URLs. We also touched upon sharding the database to optimize queries. Since I mentioned caching in my design, the interviewer also asked about LRU cache implementation.Round 4: Infrastructure (30 minutes)
This round focused on infrastructure-related questions, specifically regarding cloud platforms, CI/CD pipelines, and Kubernetes. Unfortunately, this round did not go well as I did not have much experience in these areas.Verdict: Rejected
The entire process took more than a month. I was informed that if the feedback had been positive, there would have been two more rounds: a Hiring Manager round and a Bar Raiser round. Overall, it was a valuable experience.Interview Questions (5)
Given a target string and a source string, determine if the target string exists within the source string, considering the source string to be circular. For example, if the source is 'abc' and target is 'bca', it should return true.
Given a 9x9 Sudoku board with some empty spots, check if it is valid according to the Sudoku rules. The rules are: Each row must contain the digits 1-9 without repetition. Each column must contain the digits 1-9 without repetition. Each of the nine 3x3 sub-boxes of the grid must contain the digits 1-9 without repetition.
Design a system that can take a long URL and return a much shorter, unique URL. The discussion should cover various aspects including Back of the Envelope estimations, API contract, database design, and strategies for efficiently generating random unique short URLs. Also, discuss concepts like sharding the database for efficient queries.
Implement a Least Recently Used (LRU) cache. The cache should support the following operations:
get(key): Retrieve the value of the key if it exists in the cache, otherwise return -1.put(key, value): Update the value of the key if the key exists. Otherwise, add the key-value pair to the cache. If the number of keys exceeds the capacity from this operation, evict the least recently used key.