Case study: How I passed Amazon AWS phone screen on July 8, 2019

July 14, 2019

Introduction

I was so nervous to work on online assessment two weeks ago. A lot of emotions just came to my mind in the first 10 minutes, and then I noticed that I had to calm down, and what I did to read problem statement word by word loudly. I used the technique to calm myself down. So how I passed Amazon AWS phone screen? I should not talk about algorithm, but instead I like to talk about my communication and how I improved my performance in short 60 minutes.

Case study

First of all, I always am very nice to meet people and learn things if I can. I went to Amazon AWS security group open house, what I did is to make sure that I talk to every manager, manager's manager. I never know who will be my hiring manager or I always find out that those people are very nice and helpful to answer my questions.

Most of time I ask Amazon leadership principles questions as well in those event.

How did I do in phone screen?

I read the problem statement slowly after I think that I understand the problem. That is my technique! I am trying to make sure that I understand the problem first.

Three things are most important.

1. Scalability, I discuss options available to deal with time complexity, O(nlogn), O(n^2), O(n) algorithm. I write down all options, and ask network size;
2, Object-oriented design, the function show be designed to follow S.O.L.I.D. principle
3. I can come out the solution in a minute, how to solve the problem. And also I can write the code matching the idea as well.

Actionable Items

I need to work on object-oriented design. The interviewer gave me several hints to come out good design of API. Also the interviewer reminded me a few times that I like to ask an extended algorithm. I need to make sure what I write is correct before he can move on extended algorithm.

I need to measure how much time I have in order for me to work on extended algorithm.