Amazon Interview Experience for SDE 1 (6-Months Experienced)

I applied for SDE1 Role in Amazon March 2021. Selection process completed till Mid-June. I will try to give all the details in this Article.

Apply – I visited Amazon career page, there I found some roles for SDE1 (6 months experienced). I messaged 3-5 people working in amazon for referral through linkedIn. I attached my resume and job Id in the message. And one generous person referred me for the same. In 1 week, recruiter contacted me. and I got a coding round link.

Coding Round – Coding round was of 45 min. There were 2 coding questions, both were of customized sort function. 

• In Interviews, Expectations for every coding question asked was explanation, optimized coded solution, time & space complexity. Take your time, but do every question properly. Show your perfection. There will also be interviews with only 1 coding question asked. 
• Prepare a professional scenario, instances for questions related to Leadership principles.

Round 1 – He started the interview with a small introduction of both of us. He asked about OOP concepts. He asked about my current project, learnings in my current company. He asked about vertical and horizontal scaling, small definitions. Coding questions:

1. https://www.geeksforgeeks.org/segregate-0s-and-1s-in-an-array-by-traversing-array-once/. I easily did this question in my first attempt. So, he also asked to solve this problem https://www.geeksforgeeks.org/sort-an-array-of-0s-1s-and-2s/ I did it completely too.
2. There is a manager who needs to manage tasks and schedule them. Tasks have a dependency on one another. For this, the solution was topological sorting. https://www.geeksforgeeks.org/topological-sorting/ I wrote the solution. The interviewer caught the edge case. i.e. Topological sorting is only applicable to the acyclic graphs. I missed this case. I wrote the correct code in the end. 

Round 2 – Round 2 happened on the same day. Interview started directly with the coding questions:

1. https://www.geeksforgeeks.org/length-of-the-longest-substring-without-repeating-characters/. I gave the most optimized solution in my first attempt. I did two mistakes in my code. It was pointed by the interviewer. I resolved it.
2. https://www.geeksforgeeks.org/inorder-successor-in-binary-search-tree/. This question was new to me. We both discussed for the solution. At the end, we developed O(h) time complexity solution. I wrote the solution. He was satisfied.

Leadership Principle questions: How you gained your interest in coding? What you managed the preparation for amazon with company work?

Round 3 – Interviewer was hiring manager. He started the interview with small introduction of both of us. 

• Then, He jumped to coding question: https://www.geeksforgeeks.org/add-two-numbers-represented-by-linked-lists/. I wrote the correct code in my first attempt. Then, he discussed how much the code will change, if there numbers are float. He wanted me to give answer in modular way. Discussion and writing pseudo code went long. So, only 1 coding question was solved.
• Leadership Principle questions: How you handle tight deadlines ? How you handle conflicts in work? 

I asked about my feedback to the interviewer. He said:

1. I assumed that, every node will have 1 digit. Number is an integer, not a float. Number is always positive, not negative. I should have asked these questions to him.
2. I wrote function named as “add2ll”. He adviced me to write it full as “additionOf2LinkedList”.
3. He told me the minimal code alerations for float numbers.

Round 4 – This was the bar-raiser round, most important round of the interviews. He thoroughly asked me about my work in current company.

• Leadership Principle questions: Situations, where you did more than expected? How you handle tight deadlines? 

Then, He asked me this coding question:

1. Convert given doubly linked list to spiral ordered binary tree.

   eg. 1-2-3-4-5-6-7-8
      1
     2  3  
    7  6 5  4
   8

   At first, I was giving confusing solution. Then he asked me which data structure to be used to traverse binary tree in spiral order. From there, I got the correct solution. i.e. Traversal of doubly linked list and the reverse of https://www.geeksforgeeks.org/level-order-traversal-in-spiral-form-using-deque/

I wrote the complete, error-free code in one go. Interviewer was impressed with me.

Result: Selected for SDE1 profile. Thanks to GeeksforGeeks. 

Tips – 

1. Study lots of amazon interview experiences. It will help.
2. If you covered all the edge cases in the code, and your code is correct. Then, interviewer will really be impressed with you. Dry run your code, before submitting to interviewer.
3. Give proper, complete names to function and variables.
4. If you have doubts for the question. Do ask it. Interviewers will be happy to answer.
5. Propose a solution to interviewer at first. If he is fine with it, then start coding. 
6. Think a question before-hand, that you can ask to interviewers at the end. 
7. Luck plays an important role. So, be consistent in your practice and in applying in jobs. All the dreams, will come to you one day.