Amazon Interview Experience for 6 months Intern (On-Campus)
Amazon conducted 3 rounds.
Round 1: An online assessment that consisted of 4 sections.
- Code Debug(20 mins): It consisted of 6 questions. (Cakewalk)
- Work Style assessment(25 mins): Questions based on Amazon leadership principles
- Coding(70 mins): 2 coding questions
- Count unique pairs in an array that sum to a given target: https://www.geeksforgeeks.org/count-pairs-with-given-sum/
- Find if tree S is a subtree of another tree
- Logical ability(35 mins): MCQ based aptitude questions
I was able to solve both the coding questions. 25 students were shortlisted for further rounds.
Round 2: Interview was held on Amazon Chime and LiveCode. The interviewer introduced himself and asked me for the same. After that, 2 coding questions were asked.
- Implement a LIFO data structure that has the following operations: Push, Pop, GetMiddle, DeleteMiddle.
I discussed the brute force approach using array along with the time complexities of all functions. Then, he told me to improve the time complexity of DeleteMiddle function. So, I told an approach to use HashMap. The interviewer said to make my own hashmap instead of relying on language. I was not able to come up with a solution. I was asked to code.
- Pattern-based question:
1 11 21 1211 111221
I was not able to recognize the pattern.
Round 3: Interview was held on the same platform. I introduced myself. 3 coding questions were asked in this round.
- Given an integer array, find all the numbers which don’t have a greater element on its right.
I explained brute force solution and time complexity(TC: O(n^2), SC: O(1)). The interviewer asked to improve time complexity. I told an O(n) TC solution with O(n) space. We moved on to the next question. I coded the solution.
- Given an array of stock prices, perform 2 queries.
- Change the value of the stock at ith index
- Find minimum stock price within a given range
I told brute force solution with O(1) and O(n) TC respectively. I was not able to tell the optimal solution for the second query.
- HOD of your college is supposed to give gifts to students.
Input Parameters: n(number of students), List of edges represting friends, k(cost of a gift)
If HOD gives gifts to student A, he will also have to give gifts to all the students whom A considers as his/her friend. If A considers B as his/her friend, it’s not necessary that B considers A as his/her friend. Find the minimum cost HOD will have to spend.
For example, if A’s friend is B and B’s friend is C, 3 gifts have to be given.
I told a solution based on DFS. I was asked to code. After explaining the code, he said there’s also an optimal approach. But, we were running out of time. So, he asked if I had any questions.
5 students were selected.
Hey geek! It’s time to become a success story instead of reading them. Check out our most renowned DSA Self Paced Course, now at a student-friendly price and become industry ready. And if you are looking for a more complete interview preparation resource, check out Complete Interview Preparation Course that will prepare you for the SDE role of your dreams!
Feeling prepared enough for your interview? Test your skills with our Test Series that will help you prepare for top companies like Amazon, Microsoft, TCS, Wipro, Google and many more!