I recently applied to work at yelp, and to be honest, I didn't know/remember much DS besides Arrays.

I thought I would just be asked questions on React, NodeJS, etc. Never thought it would be something on DSA.

I started leetcoding few days after I was contacted by an Amazon recruiter. Didn't cover much before I got an email from Yelp. My amazon interview was horrible as I couldn't even solve the number of steps to move the smallest element of array to the zeroth index, and the largest number to the last index problem :D.

Anyways, I started studying for yelp. The online assessment was very easy and could be done in less than 5 minutes. It was a reactjs based question to create a navBar component and make it link to some data.

After the OA, I was invited to the behavorial round. This round was great. I was asked questions on my projects, and how I work with other co-workers (Nothing to be afraid of here. Just be calm and collected. The interviewer was very chill and wanted to chat for real).

A day later, I got an email about the final round.

Mistakes I made:

• I thought I wouldn't be asked graph related questions (because I wan't really comfortable with it yet)
• I spent a good amount of time trying to solve yelp tagged questions on LC, instead of studying the topics I wasn't comfortable with
• I had assummed I might just be asked questions on ReactJS, etc.

Anyways, the first interviewer joined the room, and it felt like I forgot everything I know. She gave me two arrays containing n number of elements. The arrays will have some elements in common, and I had to calculate their similiarity score. At first, I didn't understand the question, but she explained it better to me. I had a solution in my head, but couldn't think of a better way to express it in code. The lady was kind of enough to give me some hint, and I was able to do something with the hints she gave.

Next was the system design round. I have never met a more chill interviewer. haha. The dude is the type of person you'd definitely hang out with outside of work. Sounds like he knows nothing, but he's smart.
He asked that I design a push notification system. We talked about different components that'll go into the design. Talked about the DB and schema, etc. Was a pretty chill round. Wether or not I passed it, I don't know, but the interviewer made me feel like I did.

Next was a behavorial round. Was great again. Nothing much to say here!

Final stage was coding. Lo and behold, it was a graph problem. I immediately knew I wasn't going to be able to do anything. So I intended for it to be a learning session for me. I tried to ask the interviewer for some hints, and they weren't really helpful, which I understand. My experience here wasn't that great, as he seemed more serious than the other guys, but hey, we all have different personalities, and I am fine with it.
I was given an array of objects, with source and destination. And I needed to check if there was a path from the source to the destination.

Finally, I thanked him for everything, told the recruiter that I didn't do enough to get in. Even though I know that we'd probably not do graph problems on the job, I still felt like it wouldn't be fair if I somehow got the job. The recruiter was probably shook, but I had to be honest.

Anyways, I went back and decided to learn graphs, and go even deeper. I watched a video on graphs, and was able to solve the hasPath problem in a minute ( so that was something big for me, seeing that I hated graphs).

In summary, I really enjoyed the process, and if God wills it, I'd like to try again someday. But right now, I gotta practice better that I'd be knowledgeable enough for even FAANG companies.

Anywone interviewing at Yelp, I'd recommend you learn graphs well ( just in case), and don't fret on the system designs and behavorial rounds. Also, don't overthink it. Their interveiwers are nice, but might seem very serious sometimes.

If I missed something, or if you have any questions, feel free to ask.