I interviewed at Amazon in Seattle office (March 2017) for SDE position as a part of University Hire. I think amazon started this group assessment from last year.
What is group assessment? how does it go?
They invite around 25–30 people each day. The interview process will take almost whole day. It starts with the presentation about introduction to Amazon, work culture, etc.
Next step is to divide people in the group of 3–4 people. You will be given 3 programs printed on the sheet of paper and you will need to find out the complexity of those programs and discuss in your group about which program is more efficient and why. Each group will have a person monitoring the discussion and taking notes. Group part ends here.
Next step is the programming assessment. You will be given a computer with a project in your choice of language (Java, C++, Python, etc). This project will be like some real project taken from their system. You will get a small booklet with the information on that project.
There will be 3 milestones in the interview, you will be given an empty function to finish and return the appropriate data. Implementation of this function will require you to quickly understand the project.
There will be an interview after completion of each milestone, they will ask you about your approach to solve the problem, its complexity and possible solution to make it more efficient.
Remember that the last round is bar raiser and hardly anyone finishes it on time. So don’t panic even if you couldn’t make it.
How to prepare for group assessment?
- Study the Big O chapter in CTCI for a good understanding of time and space complexities.
- Practice coding questions on HackerRank, LeetCode, CTCI, etc
- Keep in mind that the project is already there and you may not need to implement anything which is already there. E.g. Function to read a file and get some data. It may already be there, you just need to search for it first before implementing yourself.
- Lot of people waste time on trying to implement which is already there in the project. Keep that in mind.
- Working on a large project is very different than practicing the coding questions. If you do not have any industry experience, take some big open source project and try to implement few things on your own.
Hope it helps someone. Good luck with your interviews.