Amazon Interview Experience for SDE Internship (On-Campus)

Amazon Visited our campus, and they had put a cutoff of 7 CGPA on the basis of which they shortlisted students. After 2 days all the shortlisted students received an online test link.

Online Assessment Test: The round had four sections.

1. Debugging: There was a total of 7 questions in which a piece of code was written and you had to find any error so that all the test cases can pass. All the questions were very easy.
2. Coding Section: There were two questions, one was based on a linked list and the other was a logical question based on hashing, I would say both the questions were of medium level. The time allotted was 70 mins total.
3. Behavioral Analysis: This section consisted of questions that focused on your personality and behavior.
4. Reasoning Ability: This section was based on aptitude and verbal ability. The difficulty level was easy.

After this, I waited for many weeks as I knew my test went well, and then finally I received the mail for the online interview. It was scheduled just one day later.

Round 1(Personal Interview): The round began and first the interviewer introduced himself and later asked me to introduce myself which I did. After that he walked me through how the interview is going to proceed from there. He then gave me two coding questions, firstly you have to tell them your approach, and if they are satisfied enough or if your approach is the optimum approach then they will ask you to write that code in their code space which is not an editor btw. So, the two questions were:-

1. Find the square root of a number up to three decimal places of precision. So, this was a binary search question and there was an easier version of this question in which you had to find only the integer which is closest to the square root of that number, so here you had to only change your code a bit, but the logic was a bit tricky to find, but eventually, I came up with the solution and then the interviewer was quite impressed. I also had to tell the time and space complexity and also explained to them why was this the most optimal approach.
2. Given a generic tree you have to do an anti-clockwise spiral traversal of the tree. Initially, I thought that this was a tricky problem but I kept thinking out loud, and they were also able to see where and how was I thinking, later I came up with the solution and it was the optimum one, the interviewer again asked me to write how will you represent the generic tree, and then I wrote the code for the tree using a class, the interviewer was again happy to see that, later I wrote the code for the problem and also told him the time and space complexities.

I knew for sure that I was going to clear this round. After these two questions, he also asked me if I had some questions regarding the culture on amazon and I asked him a few and after that, the round was over.

After half an hour I got a call from HR that my interview is scheduled an hour later. 

Round 2(Personal Interview): The round began with the interviewer’s introduction and then I introduced myself He gave me two questions based on data structures.

1. Given a binary tree where each node has a value and a sequence of numbers, you have to find that does the tree contain any path that has that particular sequence of numbers in that order: Since I was quite comfortable with tree data structure, after some time I was able to come up with the solution and also told him space and time complexity. The interviewer was content with my answer.
2. Connect N ropes with minimum cost. I was able to come with the optimal solution and also walked them through my solution. Later I told the time and space complexity. 

The interviewer was happy with all the answers. Then, since enough time was left, He asked me some HR questions, like what are strengths and weaknesses, etc. 

After all this, he told me in the interview itself “See you soon and enjoy your day “, after which I was quite sure that I’m going to go to the next round.

Final Verdict: SELECTED

I had to wait for 10 days, then I got the mail from Amazon.