Round 1 (DSA)
Questions:
- Valid Parentheses
- Specific question not provided.
Minor variation:We are given two arrays that represent the arrival and departure times of trains that stop at the platform. We need to find the minimum number of platforms needed at the railway station so that no train has to wait. Examples 1: Input: N=6, arr[] = {9:00, 9:45, 9:55, 11:00, 15:00, 18:00} dep[] = {9:20, 12:00, 11:30, 11:50, 19:00, 20:00} Output: 3
Candidate's Approach
Completed both problems in 30 minutes.
Interviewer's Feedback
No feedback provided.
Round 2 (HLD/LLD)
Questions:
Design an e-commerce application with following features- 1. inventory management 2. handling large orders during festivals 3. add to cart, orders
He asked for basic pseudo code, database designs, API endpoints, request responses, status codes, design patterns, the strategy used for inventory management, and how concurrency would work in such a system.
Candidate's Approach
Completed all features in 45 minutes and asked for feedback.
Interviewer's Feedback
He provided a few points to consider for future.
Round 3 (HM)
Questions:
- What are the de-merits of indexing?
- Connection pooling in databases
- Write a SQL query for students with marks >= 50 in 3 subjects
- Which columns should I index according to few given search patterns for the user
- Status codes - 2xx, 5xx, 4xx and its uses
- Redis caching (discussed caching strategies and monitoring cache hit rate)
- Experience with Grafana or event trigger tools
- Chaos engineering - why to use it, metrics obtained
- Why do we use caching?
- Is Redis single/multi-threaded? How does it handle a large number of requests?
- Why do you want to join Zepto?
- What feature do you want to see in Zepto?
Candidate's Approach
Provided a brief introduction and engaged in rapid-fire Q&A about projects and experiences.
Interviewer's Feedback
Received an email immediately after the interview stating that I cleared the round and they would contact me for further discussion.