Comment by munificent | Hacker News Reader

Comment by munificent | Hacker News Reader

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College dropout here. Young people sometimes don't know this stuff either.

This is probably less ageist than it is education-ist, which is not too far away from classist.

Personally, I do think it's worth testing candidates on these pure CS skills, even though I myself didn't have them and had to study before I interviewed at Google. What I've found since then is:

1. Surprise, surprise, I actually have used quite a few of these concepts in my work. My experience may not be typical, but my role really does benefit from my having a better grounding in algorithms than I did before.

2. When communicating with other people at the company, it is very helpful to be able to presume a baseline understanding of algorithms, data structures, and big-O. A lot of code reviews and design discussions are easier and faster when you can just say "yeah, but that's O(n^2)" or "BFS would let you early out more frequently here".

As an interview technique, I also think there is some value in testing an arbitrary skill a candidate might not have, because it's a good gauge of hustle and discipline. Yeah, learning algorithms is a chore and a hassle. But... a lot of shit you have to do at work is a chore and a hassle.

If the interviewer can see that you're able to make yourself do that for the interview, it's a good sign you'll have the discipline to do some of the grunge work that is inescapable in the software field.

Of course some young people don't know the things either. If it is discriminatory against older people, that doesn't mean younger people get a free pass.

I agree with a lot of what you have said - but the issues at hand here (at least, my interpretation) is not absolute fundamentals which are obviously important.

The issue (again, my interpretation) is taking something that is taught in school, somewhat rarely applied in practice (or, is replaced by a tool/library/whatever in practice) and putting some sort of spin on it then expecting someone to be able to answer it. Or taking a problem which already has an industry-accepted solution and asking the candidate to remake the wheel in 30 minutes.

If your fresh out of school you're more likely to remember that one obscure class you took few months ago which covered some trick situation. Or you'll remember that class which taught you about that industry-accepted solution and the why behind it.

If you've been in the field for 15 years using some tool/library to solve the problem, you're less likely to remember that one obscure class you took 15 years ago which explained the origin. Or that class which covered the trick situations.

For what its worth, I don't think this is a widespread problem and very likely not deliberate when it does happen. But, I think it happens often enough that we should at least be talking about it.

I agree with your first points, but...

> Yeah, learning algorithms is a chore and a hassle

> If the interviewer can see that you're able to make yourself do that for the interview, it's a good sign you'll have the discipline to do some of the grunge work...

This doesn't make any sense, unless very, very specific bounds are put on the interview questions beforehand...

Without that, what is a candidate to do? Memorize all known data structures and algorithms?

> Memorize all known data structures and algorithms?

No, but you should know the classics. That's kind of the "general contract" for how these big tech companies interview. Most also proactively tell candidates what material they should expect to be interviewed on, like:

https://careers.google.com/how-we-hire/interview/#onsite-int...

A good interviewer is not aiming to ask gotcha questions where if you don't know that one specific weird algorithm for that one specific data structure, you're entirely hosed. That provides almost no useful signal to the interviewer.

But they will ask questions where some well known data structure is part of the solution and then provide guidance as needed based on what you seem to know.

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