Status: B.Tech from in ECE from Tier 2 college
Current Position: Software Engineer at US based digital media company
Exp: 2 years 10 months
Date: April, 2022
My resources for preparation - Leetcode and other resources past interview experiences for DS algo, youtube and medium for system design
This was my second attempt at Amazon. 4 interviews in a span of 22 days but entire process took almost 2 months
OA : standard sde2 assesment. 2 coding questions - one easy and one medium. MCQs on system design
Round 1 : DS + Coding + Algorithm [1 hr]
2 LP questions
1 DS algo question - concatenated words problem on leetcode
I was unable to solve the entire problem and felt it was tough. i was able to give solution for smaller cases but was only able to describe the approach for more complex cases.
I felt it did not go well at all and lost a lot of confidence.
Round 2 : HLD [1 hr]
First 20 minutes, LP questions.
Design throttling mechanism/rate limiter - interviewer was more interested in the system around the rate limiter rather than algorithm used to create the rate limiting. lots of follow ups were there and it was a good round
This round went well and was a boost in confidence.
Round 3: coding with hiring manager [1 hr]
First 20 minutes, LP questions.
b) 1 DS algo question - i didnt find it online but i will try to explain the question
given - array of strings in the format -> [ 'firstName#lastName#skill_1skill_3' and so on ].
input - skill name
output - names of people who have this skill
easy question and can be done by splitting and storing info in map. there were lots of follow ups like what will happen if more than one skill is given in input.
This round also went well and had some good discussions with the panel.
Round 4 : coding [1 hr - Bar Raiser]
First 20 minutes, LP questions.
1 DS algo ques - boundary traversal of a binary tree (i had done it as it was there in the past interview experiences of amazon)
After a few days, i was selected.
offer - https://leetcode.com/discuss/compensation/2020203/Amazon-or-SDE2-or-Bangalore
Key Takeaways:
Have your LP answers ready before hand. This may seem like homework and useless work but these hold almost 50% wieghtage. Take one full day and note all the possible LP ques from the doc shared with you. write complete answers for each and everty one of them and revise them as much as possible as they have a lot of weightage. There is always follow up questions on your answers so make sure it is a true story and you know all the facts.
Be confident during problem solving and always keep on speaking your thoughts. try not to be silent and thinking for long periods.
The most helpfull resource for me was past interview experiences for sde2 and sde1 amazon during the last 1 year. There is a very high chance of you encountering a similar question as these experiences. By doing these random questions you will automatically brush up the concepts behind these questions.
design is a very good way to cover one bad coding interview. coding interviews usually have one right answer but design rounds dont have any answer. they are just a discussion of some desing concepts. even if you design a wrong system, interviewer will try to drive you in the right direction by asking questions about something you messed up. this will give you a hint that you missed something important in your design. Make sure to pick up these hints.
one bad interview doesnt mean the process is over.
sometimes if your LP ques part is good and coding part did not go well even then you can clear that interview. This just goes on to show the value that LP ques hold.