Profile
Status: 6 years experience (currently working in service based MNC, previous experience at product based startups and service based MNCs.)
Interviewing for:
- Position: SDE2 at Amazon
- Location: Bangalore, India
- Date: October 2021
Interview
Round 1 (Online Assessment) -
[Received link on Sept 30, 2021 - completed on Oct 6, 2021 (you get 1 weeks time to complete the assessment.]
Online assessment has 3 sections, the first section was a coding test on HackerRank and the second section was System Design level MCQs and third section was a work-style assessment test. Total time required is around 2.5 hours.
Coding Test: (90 mins)
Q1: Minimum Number of Flips required to create a coin pattern. Similar to this: https://leetcode.com/problems/flip-string-to-monotone-increasing/solution/ [LC Medium]
Q2: Similar to this: https://leetcode.com/problems/minimum-swaps-to-make-sequences-increasing/ [LC Hard]
I was able to solve both of these but 2 test cases were not passing for Q2. Anyhow submitted my solution as the time was running out.
System Design MCQs: (Around 30mins)
Around 20 questions around system designing and selection of technologies or technical methods for a given scenario. Easy to solve if you are a experienced developer.
Work-Style Assessment: (Around 30mins)
Few MCQs containing behavioural questions. Just to check you are a cultural fit.
Received a mail on Oct 11, 2021 stating I cleared the OA and will have Onsite rounds on Oct 23, 2021. Contactd the HR to ask for a bit more time but they she was not able to reschedule as the requirement was urgent and they wanted to get the process done faster.
Virtual Onsite Interviews - (Coding, LLD, HLD and LPs) - Oct 23, 2021
Round 2 (HLD round by Hiring Manager - 1 hr):
Started with introduction, then moved towards LPs.
2 LP questions went on in detail for almost half an hour.
System Design: Was asked to design a Bus booking system. First discussed all the components and their flow. Once satisfied moved with drawing the High level architecture.
Follow-up: Was asked to scale up. I guess I messed it up a bit.
Round 3 (LLD round - 1hr):
Asked to design chess game. Lots of follow up questions. Was required to code with OOPs concept in mind. I was able to come up with satisfactory answer and also answer the follow up questions well.
This was followed by LP questions for last 15mins. Went pretty well according me.
Round 4 (Coding round - 1hr):
The interview started with introductions (5mins), followed by 2 coding questions (40 mins) and then 2 LP questions (15mins).
Q1: Slight modification in: https://leetcode.com/problems/find-minimum-in-rotated-sorted-array/ (LC Medium)
Q2: https://leetcode.com/problems/merge-k-sorted-lists/ (LC Hard)
I was able to solve both the questions with optimal approach. Needed a bit of help from the interviewer to come up with optimisation for Q2. This section took a bit more time, so was left with only 7mins. I was asked 2 LP questions in this without any follow up.
Preparation Strategy
For coding: https://leetcode.com/list/xjbs5ace/. This is not the list from where you receive questions, but as I was short on time, this list helped me filter out the questions on varied topics and revise quickly. Really appreciate the efforts of LC Community and hence trying my bit to give back for all the aspiring members.
For system design: https://github.com/donnemartin/system-design-primer and YouTube videos on different system designs.
For LPs: https://leetcode.com/discuss/interview-experience/1149636/Amazon-LPs-Compiled (Followed the STAR method and prepared my answers for these questions. It was enough according to me.)
Verdict
Awaiting results.
The HLD round went a bit bad, hence nervous about the results. :)
Any suggestions on whether I should follow-up or wait a bit?
Also suggestions on improving my post are most welcome. :) This is my first such post, so sorry if I missed anything.