You consider that a "data structure question"? Honest question - I would (do) characterize it as a sort of "fizzbuzz+" that is deliberately NOT data-structure-y, and I'm surprised by this response. Can you give an example of short coding tasks you would consider not data-structure-y?

(For the record, we do ask about DBs and system design in other sections of the interview. The coding is one portion of three for the interview as a whole.)

Minesweeper is all about storing data about the board and displaying the numbers is all about running through data. Seems very data structurey to me but maybe that's non heavy dev side coming through.

Maybe I'm just thinking too much problem, overloaded my small attention brain and misread it. I wouldn't call Fizzbuzz data structure-y however.

I'm also mostly outsider looking in. Never worked at FAANG and working with YC companies, I come on much later and tends to be more keeping the lights on and stopping the duct tape rocket from exploding.

I disagree. Minesweeper doesn’t require anything more exotic than a 2d array of enums. This is bread and butter stuff that you’ll run into in 99% of programs. If someone doesn't know how to use their language’s lists, enums and structs, I don’t think they know the language yet.

A “data structure problem” would involve more exotic data structures, usually of the kind the candidate has to implement themselves. For example, b-trees, heaps, skip lists, and so on.

The reason a lot of people don’t like custom data structure questions is that they come up rarely in most people’s jobs. Lists, structs and enums on the other hand are used everywhere. Your programming job will almost certainly require you to understand them.

I'm a competition programmer so my perspective is generally miscalibrated, but part 5 is usually solved with a BFS. You can say BFS is basic, and it's maybe the part of competition programming that comes up more often than any other in real life (tied with sentinels, which you usually use in your BFS?), but I think it's a "data structures" problem.

If this test is calibrated like the triplebyte programming challenges, less than 1% of people will finish part 5 in the time given. I think when I was interviewing, only about 3% of people reached step 5 at all. Finishing was super rare, and it really only existed to separate the top couple percent. (And yes, we told the candidates that we didn’t expect them to finish in the time allocated). It doesn’t matter if step 5 is harder. Most people will never attempt it anyway.

But even then, while BFS would definitely work here, so would DFS and that’s simpler. A simple, unoptimised recursive DFS flood fill would be like 8 lines or something given by that stage you already have a function to reveal a cell. You just have to call it on all the adjacent cells. I don't see that as a data structure problem. You could argue it’s an algorithm problem, but it’s about as easy as those come.

Got me there! The situation where you already have that stuff definitely favors DFS and makes it pretty trivial

I think its because the person is thinking you are looking for something especially smart when in fact something like a list of lists would be fine enough, if you can explain the tradeoffs for using them.

Edit: beaten, yes they were overthinking it.

Yep. Am bad at Dev. Pretty good at making sure Kubernetes cluster doesn't implode though.

I think you are selling yourself short - the problem is just some minor education to realize you probably know most of what you need to know. And I still cant figure out how to get a kube cluster working.

the problem is embedding game logic (game rules) into the matrix, which is a data structure, hence it is a data structure question

You don’t need to embed game rules into the matrix to solve this problem. (What does that mean anyway?) Just store the board in a 2d array of some sort and write some functions to interact with it.

>> store the board in a 2d array of some sort and write some functions to interact with it

thereby making it a data structure problem

That’s just not what a “data structure problem” commonly means. If it was, all programs would be data structure problems because all programs interact with data in some form.

A data structure problem is a problem where designing and implementing an appropriate data structure is in some way hard. A 2d array doesn’t fit the bill. It’s not exotic enough.

> If they can't do Data Structures, are they worthless to Silicon Valley companies?

I think you might be overthinking this - understanding how to model a problem with a data structure is a core competency of any developer. This isn't a "gotcha" question where you need to know union find sets or how to invert a linked list in place.

If the question was rephrased, "design a JSON schema for the state of the board" would you know how to approach it? Because that's essentially what step 1 is asking.