Amazon WOW Interview Experience

I registered on the official page of Amazon Wow during July 2021. There were regular updates regarding the webinars organized by Amazon Wow. I attended those and came to know about the online assessment for two month internship that would begin in May/June 2022. 

Round 1: Online Assessment 1: It was taken on Mettl platform. This round consisted of 9 sections.

• CS Fundamentals – OS, DBMS, DSA, OOPS, CN, Time complexities 
• Pseudo codes –  Candidates had to find the outputs for the pseudo codes
• Software testing 
• System Design 
• Software Management concepts
• 1 coding question was also asked which was of Easy level.

After two days, I was asked to apply to the company’s job portal and I received the link for the second online assessment.

Round 2: Online Assessment 2: The assessment consisted of four parts:  

• Code debugging section-  There were 7 questions to be solved in 20 minutes. I solved all the questions and all the test cases were successful.
• A coding test- There were 2 questions to be solved in 70 minutes. The coding questions were based on Greedy algorithm and Dynamic Programming. I was able to solve one question completely and the other question partially. 
• A workstyles assessment- Multiple choice behavioral questions (20 minutes) 
• Reasoning ability section- Around 24 questions to be solved in 35 minutes. 

After ten days I got the mail stating that I have cleared the Online Assessment. A survey regarding the interview dates was sent to the candidates who got shortlisted. For the two month internship candidates, there was only one round of interview.  I chose October and my interview was conducted. I was sent the link one day before. It was mentioned that the behavioral questions will be focused on the Leadership Principles of Amazon. 

Round 3: Virtual Interview: I joined five minutes before the beginning of the interview. The interviewer introduced himself first and then asked me to introduce myself. I gave a brief introduction including my technical competencies. Then he dived into the coding questions. 

• This was the first question: https://www.geeksforgeeks.org/find-first-non-repeating-character-stream-characters/

I solved using the queue approach, then the interviewer asked me to solve it in O(1) space. It took me some time to come up with the Doubly Linked List approach. I asked him for a few hints, and he patiently listened to my approaches.

For the next question, he asked me about my favorite data structure. I told him that it was Trees. He asked me some theoretical questions on Binary Trees and I was asked to code the following question. The interviewer did not directly say that I had to find the width of the tree. After asking him some questions to get more clarification of the question, I realized that I have to find the width of the tree. https://www.google.com/amp/s/www.geeksforgeeks.org/maximum-width-of-a-binary-tree/amp/

I also had to dry run my solution to check whether the edge cases were being covered.  The interview took around one hour and five minutes. After that the interviewer asked whether I had any questions to ask him. I asked him regarding his work at Amazon. 

Verdict: I was selected for the two month internship and now I have received the PPO after the successful completion of my 2 month internship this summer.

Tips:

• Keep communicating with the interviewer, tell them about your approach. By doing this, you can avoid misunderstanding the question. 
• Always dry run your solution to check whether the edge cases are being covered or not.
• If the question is not clear enough, do not hesitate in asking you doubts. Ask about the constraints as well.
• Leadership Principles of Amazon are important. Do not forget to go through them before your interview.