How can I be best prepared for Amazon's technical interview in the next 15 days?

Answer 1:
I went for my Amazon technical interview with only 5 days worth of preparation and still got the job. Here’s the story -

The Phone Interview

I got a call from Amazon and they were interested in a phone interview. I asked them to schedule it 2 weeks from the day they called but they had a hiring event drive coming up and asked me to take the interview within 3 days.

I was never good with data structures and algorithms or technical interviews for that matter because my bachelors was in electrical engineering. However, I have been working as a Software Engineer for the last 4 years so I can definitely code really well and I am aware of the various design paradigms you require to write good quality code

Now, with absolutely no knowledge of how a graph or a tree works OR how a merge sort would sort data, I devised a simple plan for myself. I spent the first two days on HackerRank practicing every data structure. I did not practice all the questions, but just the ones I thought were important
On the 3rd day , before the phone interview, I solved couple questions from Cracking the Coding Interview and went over every data structure which is commonly asked in interviews.

Now come the day of phone interview, I was able to solve the one slightly hard question my interviewer asked. I was obviously stuck at places, but I made sure to keep saying whatever came to my mind, so he knew how I was thinking. And it worked, because me and my interviewer did a bit of pair programming to solve the question.

Technical Onsite InterviewNow I was invited to the onsite BUT I only had 5 days to prepare for it. Instead of starting from the first day , I went on a two day trip to Vegas (Not kidding). I started on the 3rd day and followed the same routine of solving hackerranks and cracking the coding interview. I did not spend all day on it, just 3–4 hours a day when I felt I would focus the most

You must be wondering this is too good to be true, cracking the interview with such little preparation. Trust me I wonder the same. But there is something I practiced the day before my interview, which I believe is the secret sauce that helped me do well - /

Secret Sauce

• Step 1 - I really focused and improved upon how I START thinking about the question. This is the most important step according to me. You may know all the data structures in the world, but if you dont start off correctly with a problem, you cant do much. So first step is to just think about how you will start!
   In my case I started of by writing all the inputs given to me, all the outputs required and constraints if any
• Step 2 - What next? Well now think which data structure will solve the problem?
• Step 3 - Is there something you should do before using the data structure? Like sorting, arranging, or anything that makes the it easy for the data structure to solve that problem. More often than not, sorting a given input can do wonders
• Step 4 - Write down all the steps you will be performing. Don’t even think about writing code right now. Just write the steps and write the expected Big O complexity and space complexity
• Step 5 - Now optimize the solution you wrote above. Were you at least able to write a brute force? Can you use another data structure to improve the complexities ? Can you pre-process the input to reduce the complexities?
• Step 6 - Only when you are absolutely sure about the optimal solution, start writing the code.

Although the amazon interview was very challenging and not easy at all, I stuck to my steps above.. even when I was nervous as hell. Also, I prepared for my behavioral questions. Please dont think behavior questions dont count. They really do

Repeat these 6 steps during your whiteboard too and you will succeed. I got three job offers apart from Amazon after i used the above approach . And trust me my preparation was bare minimum (like 1–2 days at max)

Answer 2:

I'm the Former VP Global Talent Acquisition for Amazon and trained interviewers at Amazon on how to interview, so this is a topic I know well. In fact, too well--there is some non-public info I cannot disclose.

However, the generally public information I can disclose will help you get prepped for your Amazon interview.

First of all, you didn't say whether it was a phone or in-person interview. Given that it is 15 days out, it likely is an in-person interview.

In either case, you need to read and re-read all of the information you can get your hands on regarding algorithms (many of the tech questions are based on algorithms, not specific languages) and data structures. You need to have one language where you have a level of mastery, ideally two or more (so that you can select the one that matches up best with your interviewer). However, don't worry if the interviewer is not familiar with the specific language you use to solve a technical problem, it's the algorithms and data structures they will be looking at in your answer.

If you are doing an in-person interview, be ready to whiteboard an answer. You need to talk as you write out your answer to show your logic in working out your answer to the problem. Even if the interviewer has not suggested that you use a whiteboard to solve the problem, almost every interview room has one. If there is one in the interview room, ask if you can use the whiteboard to solve the problem.

Your in-person interviews will typically be 30 to 60 minutes each and each interviewer (usually 5-7 interviewers for tech) will be focused on a different competency. Don't expect all interviews to be technical. You will also be asked behavioral-based competency questions. Answer using: "Let me give you an example..." and then provide your best example.

At least one person on the interview team will likely not be from the team for which you are interviewing. If you are interviewing with multiple interviewers from two or more teams, you may be interviewing for roles in more than one team. The "odd out" person person from a different team (usually a senior person from another team) is a Bar Raiser and they are on the interview slate to make sure that the interviewing team makes the right overall hiring decision, raising the talent bar at Amazon.

If one interview (or even two) don't go well, don't worry about it. You can still get an offer even if you blow one interview. Although the exception could be the Bar Raiser.

Overall, use specific examples of work you have done before to show how not just how you would solve a problem, but how you have solved a similar problem in the past. Use the S-T-A-R behavioral approach, giving a Situation or Task, the Action you took and the Results achieved. Try to stay away from hypotheticals and use real life examples whenever possible.

Amazon has a very high bar for tech hiring, similar to Google. Be ready to be tested to your limits and (depending on the interviewer) possibly beyond your limits. The interviewer may want to keep pushing technical boundaries to find out what you don't know, in addition to what you do know. So you might walk away thinking you blew the interview because you couldn't answer their last question, when in fact you went to a pretty high upper limit to find a question to which you didn't know the answer.

The entire day (usually in-person interviews are at least a half day, sometimes a full day or even longer, depending on the role) can be pretty grueling and demanding. You need to be at the top of your game all day long. Get fueled up before going in.

And oh, BTW, if you need the bathroom, you'll probably have to ask to use it. Most interviews are arranged back-to-back-to-back with no breaks in between. Better to ask than squirm in your chair. :)

It's unlikely that you will get feedback same day. There is an interview debrief that will take place with all interviews, can be later that day, but is usually a day or two later. After that meeting is when you will hear back from either the Recruiter or the hiring manager about next steps (either an offer, a decline or, in some cases, further interviews). And a no doesn't necessarily mean no forever. You may still have a chance (if the hire/no hire decision was close) to interview with a different team where you may be a better fit. So keep the doors open.

(source Quora)