Amazon Interview Experience for SDE 2024

Amazon Offered a 6M SDE Internship for 2024 Batch i.e. from January to June 2024. It was part of an internal student program and we directly received the emails for applying for this internship. After that, the following process continues:

There were 2 Rounds:

ROUND 1: Coding Online Assessment

• No. of Questions: 2

1. To find the number of subsets having an average equal to the given average value k.
2. To compute the minimum number of question marks required for matching all the strings.

• Time: 1 hour
• Difficulty Level: Medium
• Platform: Hackerrank

Those who were able to solve both questions correctly were proceeded to the next round.

ROUND 2: Online Technical Interview

The interviewer started with the usual About you question and then directly jumped to the coding questions. He explained it to me the question, then explained it through a sample test case. And then asked me to first explain the approach and if he was satisfied with the approach, then only I can code.

• No. of Questions : 2
• Duration : 60 minutes
• Platform : Amazon chime
• Difficulty : Medium

1. To compute the cost of merging the given number of Alexa devices where the cost of merging any two devices was equal to sum of diameters of both the Alexa devices. (Similar to : connect n ropes minimum cost problem on GFG ).
   Firstly, I gave him the recursive brute force solution to find the minimum cost by considering every possible subsets. This was a exponential time solution. Then he asked me to optimize it. Then I gave him the iterative solution where I used sorting with each iteration with time complexity O(N*Nlog(N)) and space complexity O(N). Then he requested me to make it even better. I used the concept of priority queue to avoid sorting again and again , Now my time complexity was O(Nlog(N)) and space complexity was O(N). Now he was satisfied with the approach and asked me to code it.
2. To clone a doubly linked list using random pointer.
   Firstly I gave him the solution using hash map and storing data of each node. But then my solution was not appropriate for solving scenarios in which duplicate nodes were present. It was difficult for me to come up with the solution at that time for this scenario and I told him. Then, with his assistance, I was able to come up with a workable solution after he provided me some recommendations. After that, we had some discussion that how my solution will always give the correct solution. After that, he asked me to code it, which I was almost done with but he told me that time is up and if I have any questions.

Key points:

• The interview was not only focused on just solving the given problems but also to analyze the process or way of approaching the solution.
• The interviewer was very helpful . He showed me direction in between wherever I got stuck. I was interacting with the interviewer constantly.
• I would suggest to practice DSA as much as possible in depth, How to analyze time complexities and then their optimizations as well.
• Also focus on loud thinking i.e. speak up whatever you are thinking while solving a problem. Don’t let the interview a one side communication or just a question-Answer session. Rather keep discussing things and make it interactive.