Amazon Interview Experience | Set 157 (On-Campus)

Online Round
Initially a test was conducted on hackerrank on the basis of which students were shortlisted. The test contained 22 questions, 20 Gate like MCQ’s and 2 Programming questions. The MCQ’s were on OS(page replacement policies), output, trees etc.

The programming questions are as follows :
1) Maximum of all subarrays of size k
10 Bonus marks were there if one could solve in O(n) time.

2) Given 3 numbers in the form of linked list. Give the sum of the 3 numbers as another linked list.
Example: 1->2->3 + 2->1->3 + 3->2->1 = 6->5->7.
A slight variation to this question :
Add two numbers represented by linked lists

They shortlisted around 30 people for the interviews. Since some of them got placed on day 1, they were extending the shortlist on realtime also. There were 4 rounds in total. Every round was an elimination round. In each round, I was asked to explain the algorithm as well as implement it on
the paper. Every interview started with the typical “tell me about yourself” ice-breaker.

Round 1 (Technical)
1) Finding LCA in BST.

2) Finding LCA in Binary tree

3) Product array puzzle

Round 2 (Technical)
1) Spirally traversing a matrix
2) You are given ‘n’ appointments. Each appointment contains startime and endtime. You have to return all conflicting appointments.
3) Some basic discussion on memoization and dynamic programming.

Round 3 (HR + Technical)
1) Tell me about yourself.
2) Why Amazon?
3) Where do you see yourself after 3 years.
4) What are your weaknessess? I said one, he asked me one more?
5) Lot of questions on my intership project and on the technology used in it, challenges that I faced, best thing I liked about the technology etc etc.
6) Some question on my hobbies.
7) Finding LCA of a tree whose nodes has only parent pointers.
8) Implement a stack from 2 queues.
9) Implement a queue from 2 stacks.
10) Design classes for a Snake and Ladder game. The focus was on OOPS concepts.
11) Some more question on my projects and resume that I don’t remember.

Round 4 (Technical)
1) Rotating an array. (All approaches)

2) Search an element in a sorted and rotated array

In all the interviews, the approach is seen, so taking out loud what you are thinking is must. Its good to point out the problem(s) that are the crux of the question and solving it would lead to the final solution. The interviewers are always very helpful, they give hints whenever required. Just being calm, composed and patient during & between interviews and studying geeksforgeeks will do the work.

All Practice Problems for Amazon !