Amazon Interview Experience for SDE (On-Campus)

Online Test: There were 4 sections in the online test which was held in the month of August.

• Debugging questions (Easy)
• Coding Questions (Easy-Medium)
• General Aptitude Assessment (Easy)
• Workstyle compatibility test (Read Amazon Leadership Principles to answer accordingly).

I did both questions in the coding round and was hopeful of clearing the online assessment.

Round 1

• My interview was in the afternoon, I joined earlier than my interviewer. My interviewer was currently a Software Development Manager and an ex-Vice President at Goldman Sachs, I was quite nervous after stalking his LinkedIn profile. Anyways, so he joined and he was very polite while talking. He asked me for an introduction and I told him about myself. I mentioned my interest in sketching and astrophysics and then we had a mini discussion on that. That kind of established a rapport with him.
• Then we jumped to DSA problems and he asked me a problem on finding the first index of the non-repeating characters in a string. I told him an approach using the hash map of time complexity O(N). He seemed satisfied by my approach and asked me to write the code. While writing code, he put a lot of emphasis on clean code and in the end made me change the variable names to improve readability. I learned a lot from that.
• After that, he asked me a variation of rotten oranges which was about finding the time by which all patients in a ward will get COVID infected, given there are three types of cells: [0]-with no patient, [1]-Patient with some disease except COVID, [2]- with COVID patient
• I did it with the approach of multisource BFS. The time complexity of my approach was O(m x n).
• In the end, the interviewer asked me to ask some questions and I asked him about his experience at Amazon and “How he start with something new which is a requirement for a project he has been allotted”. After that, he told me “it was great interviewing with you” and ended the meeting on a positive note. I was pretty confident that I will be selected for round 2 but didn’t get any notification regarding it the whole day. The next day, HR called me at noon and asked me to join the meeting immediately.

Round 2

• My interviewer was already present in the meeting, I introduced myself and she asked me few questions on internships and one of my projects. The questions she asked were based on DBMS (“Why did I use MySQL in my project?”, NoSQL, Scaling). Then she started asking coding problems.
• Merge K Sorted Linked Lists.
• Find total number of (i,j) pairs in array such that i<j and a[i]>a[j].
• I could only answer the first question and code it. She seemed satisfied. Then she asked me to just explain the approach to the second question but couldn’t come up with an optimal approach for the second one. She asked me to end the interview as no time was left. I asked her some questions on “What she likes best about working at Amazon?”, “If a new technology is a requirement for a project allotted to the team, how do you guys go about working on it?”, “
• Do you have some feedback for me that I can improve upon in the future”. On the feedback question, her reply was positive but I had doubts since I couldn’t answer the second coding question.

Verdict: Selected

Tips:

• My final advice would be to believe in yourself and answer with confidence. If at any point you realize your approach is wrong then be honest and humble. Smile, be polite, and try to think out loud.
  Also, solve as many previous interview questions as possible.