Round 1
Questions:
- 2 Leadership Principles (LP) questions (prepared with stories).
- Low-Level Design (LLD) - Design Amazon Locker.
- Constraints: locker and package sizes are S, M, L. A larger locker can be used if the right size is not available for a package.
- Required to write 3 classes.
- Additional task: Write code to retrieve a package by user input (locker number).
Candidate's Approach
Wrote the classes in approximately 10 minutes. Implemented the code to retrieve the package by user input, which took a couple more minutes. The interviewer acknowledged that the code was correct and engaged in an off-topic conversation afterward.
Interviewer's Feedback
No feedback provided.
Round 2
Questions:
- 2 Leadership Principles (LP) questions (prepared).
- Coding - Jump Game II & IV.
- Started with Jump Game II, wrote the code in ~5 minutes.
- Tweaked to Jump Game IV, which was unfamiliar. Took 10 minutes to write the solution.
- Follow-up question: "Does it look like DFS?"
Candidate's Approach
Wrote the solution for Jump Game II in about 5 minutes. For Jump Game IV, took 10 minutes to develop the solution. Initially did not recognize the DFS aspect but acknowledged it upon prompting.
Interviewer's Feedback
No feedback provided.
Round 3
Questions:
- 2 Leadership Principles (LP) questions (detailed exploration of one story).
- Coding - Trapping Rain Water problem.
- Solution using prefix and suffix array in 10 minutes.
- Follow-up: Asked if the solution could be optimized to avoid accessing arrays twice.
Candidate's Approach
Implemented the solution using prefix and suffix arrays in 10 minutes. When prompted about optimization, proposed a two-pointer solution, which was almost complete when the interviewer decided to conclude the round.
Interviewer's Feedback
No feedback provided.
Round 4
Questions:
- 2 Leadership Principles (LP) questions (one question about fighting to get something done at work).
- System Design - Design a product for near real-time data consumption from tens of thousands of devices to compute min/max values.
- LLD was intentionally vague, with many clarifying questions asked.
- Interviewer provided vague answers and displayed strange behavior during the discussion.
Candidate's Approach
Started with database design but was redirected by the interviewer. Asked many clarifying questions, but received vague responses. Drew a diagram and explained the design despite the interviewer's confusing behavior.
Interviewer's Feedback
No feedback provided.
I received an email 3 days later stating that I was rejected and that my cool-off period is 1 year. I inquired if I only failed the System Design round and requested detailed feedback, but received no response.