Status: B.Tech from Tier 3 College
Current Position: Software Engineer at Mid Size Product based Company
Location: Bangalore, IN
Exp: 5+ Years
Date: March, 2022
First of all, I would like to thank Leetcode community, without this forum I would have never got this offer. Let me first share my interview journey then some learnings along the way.. I won't be able to share the exact questions but I will mention related topics.
This was my second attempt at Amazon. Interview process took more than a month which can become frustating if you are waiting for response from recruiter after each round. But it also gives breathing space and more time to focus on each round.
OA : This was skipped for me as I did well last time I believe, recruiter told me that you will have only onsites.
Round 1 : DS + Coding + Algorithm [1.5 hrs]
a) First twenty minutes LP questions.
b) Two LC medium type questions.
Q1: Array based question.
Q2: Scenario based question, interviewer gave me a vague question and after some follow up questions I was quickly able to identify the pattern which uses binary tree traversal + map.
c) Some question related to general large input for both question, coding standard, handling corner cases etc.
Self Evaluation: Interview went for more than 1.5 hrs than scheduled 1 hr and I knew that it went well and I was confident.
Round 2 : HLD [1 hr] with 2 managers
a) First 20 minutes, LP questions. And this time I stumbled with some of the LP questions. I thought I bombed this.
b) Standard HLD design question and lot of follow ups.
Self Evaluation: After HLD question, I started feeling more confident as I did well but I knew my LP answers were not up to the mark. But HM was very much happy and really interested in my next set of interviews.
Now here is interesting part, I had prepared some good questions to be asked at the end of interview and with two managers in same interview, I got a chance to know more about Amazon and their internal process/culture and had a good conversation with both of them.
Round 3: HLD + LLD [1 hr]
a) First 20 minutes, LP questions.
b) HLD + LLD question. First 10 minutes, I need to draw a High Level design and explained each component. Then interviewer asked me to implement some of the feautures. Used some Design pattern and made sure I speak up loud, why I used them. Some more follow up questions.
Self Evaluation: It went really well and I was able to answer almost all of the questions.
Round 4 : Problem Solving [1 hr - Bar Raiser]
a) First 20 minutes, LP questions.
b) Hard Level question. When I got the question, It seems hard to me and was unable to get any idea. Then I started with brute force and then optimized a bit using hashmap & came up with O(n) solution, but Interviewer kept asking me is there any more optimzed solution. I asked him if he is looking for log n solution. I was looking for a hint as I was getting some intuition but he denied revealing anything. He asked me to write solution whatever I could come with up. I quickly coded and explained the solution.
After few minutes he told me, he is done with his question. No more coding question to be asked.
c) I asked some questions at the end of interview.
Self Evaluation: I felt my chances are very dim after this round as Bar Raiser has veto power in hiring decision and I just bombed this round.
[After interview I searched for this question, couldn't find anywhere. Some stackoverflow answers suggested log n solution using BST and I was correct but couldn't think at that time ].
After a week, recruiter called me and congratulated and that's it :)
Key Learnings:
- Keep your LP answers ready, we invest months/years for coding round but I think LP questions are very important for Amazon.
- Always drive the interview. If you are not driving the interview its a red flag.
- If interview goes beyond scheduled time, it is a positive sign.
- Prepare for LLD + HLD, I got rejected because of these in my first attempt.
- Always ask questions at the end of interview, its a good chance to impress your interviewer.
- Believe in yourself, if I can do it, anyone can crack interview.
- I have solved around 1100+ Leetcode problems, but not able to get higher ratings always pulled back my beliefs. I had just solved once all 4 questions in LC contest but usually I will solve 2-3 problems. Sometimes with so many penalties.
- Spaced revision is very important before interview for important topics or concepts.
- LC premium helped me a lot.
At the end, again I would also like to thank some of leetcode heroes.. (votrubac,lee215,hiepit,fun4leetcode,bakerston,jeantimex and others.)
Believe in your journey, there always be tough times for whatever reason. All the best for your interview!