Amazon Interview Experience for SDE Intern (Off-Campus)

Online Assessment Test: The round consisted of four sections.

1. Debugging (time constraint): There were 7 questions to be debugged.
2. Coding Section (time constraint): There were 2 coding questions, one from trees and the second one from array. The difficulty level of the question was medium – easy.
3. Behavioural Analysis: This section consisted of questions about work and behavioural related ones.
4. Reasoning Ability (time constraint): This section consists of some verbal reasoning questions and some aptitude questions. The question level was easy.

After the online assessment, I received a mail that I have been shortlisted for interviews, there were basically 2 rounds to be held and all were elimination one, this detail was given in the shortlisting email itself.

Round 1(Personal Interview): The round started with little greetings and then I was given my problems.

1. Find the bottom and top view of the tree.

   1. Bottom View of a Binary Tree.
   2. Print Nodes in Top View of Binary Tree.

   Basically, I needed to tell the approach of both of them and then I was asked to code the bottom view of the tree, I was able to tell the approach and code it.

2. Find the Maximum sum such that no two elements are adjacent. The problem I received was not exactly the same instead of array I have to take the level order sum of a tree, I was able to solve this problem and was able to code the problem. 

The interview ended with the introduction and some questions that I asked them regarding amazon and its work culture.

After this round, I received a call from hr regarding the second round.

Round 2(Personal Interview): The round started with an introduction and then I was given my problems:-

1. Find the first non-repeating character in Queue based approach for first non-repeating character in a stream. I was not clear with the problem, so I asked a lot of clarification questions regarding the problem then I told him my approach, and he was satisfied with the one, then I was asked to code it which I was able to code.
2. Find the minimum time which would take the gas to reach all the cells if the explosion happened at a point in the matrix. Check if all enemies are killed with bombs placed in a matrix. The problem was simpler than the given link, it was a simple BFS problem, but I was asked why we are not able to use DFS here, then I was asked to code the problem.

Then the interview was over, and after a few days, I received a mail regarding the selection. My overall experience was really great the interviewers were really cool and helping people, really excited to start working there.

Thank you for reading!