Comment by stcredzero | Hacker News Reader

Comment by stcredzero | Hacker News Reader

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San Francisco strikes as one of these low-tolerance / high-discrimination places.

The rapidity with which people flip the idiot bit on you, due to puddle-shallow signalling in the Bay Area really takes my breath away.

- The sound of keys clicking in a phone interview automatically means you are Googling the answer in an interview. Never mind that you are a dynamic language programmer and you are writing a 10 second scriptlet to answer the question.

- The mention of anything that sounds "audiophile" automatically means you are a terrible douche who naively believes in all of Monster Cable's woo. No need to actually evaluate what you are saying through knowledge of physics.

- You must subscribe to the magical powers of [insert paradigm/language here] or you are a dirty mudblood who's simply too dim to appreciate the magic. (Don't say anything like, "Soft factors, like how well your team works together, swamps the effect...")

- You must be able to mad-libs complete the paraphrase of recent CS textbooks, or you obviously never covered the topic.

This isn't even to mention weird prejudices and half-baked knowledge about older technologies. It's as if people didn't understand that https://news.ycombinator.com/item?id=5695816 is also a parody of programmers misunderstanding of technology.

> "You must be able to mad-libs complete the paraphrase of recent CS textbooks"

This kind of thing is the worst in interviews. Like getting asked some fill-in-the-blanks question on the pillars of OOP or to define some random bit of jargon or what-have-you. That coupled with the "have you seen this question before" interviewing is just infuriating.

I just took the TripleByte assessment for Mixpanel and over half of it was this kind of shit. Worse, they threw in multiple-choice design questions. No, I would not use any of the complicated sets of things you presented me in this case, and do not think any of them is the right answer.

I love this one: Once I was asked a design question. I presented three answers. Then the interviewer says, "Well, here's how I would do it!" (unspoken: you idiot) He then proceeds to write out my second option. (The takeaway: If you don't understand someone's jargon, you need to be curious and ask, don't just gloss over it.)

> If you don't understand someone's jargon, you need to be curious and ask, don't just gloss over it.

Quite frankly understated.

> That coupled with the "have you seen this question before" interviewing is just infuriating.

When I interview someone, I will usually ask if they've seen the question before, so that I can skip it -- is there something wrong with that?

Yes, because this gives them the chance to say no and pretend to walk through it slowly showing how "smart" they are.

How is that any different from the potential behavior if one didn't ask?

> "have you seen this question before" interviewing

I suspect that this was meant to refer to interview questions with an "Aha!" answer, that are unlikely to be answered correctly by people who don't already know the answer.

For example, I think, "How would you detect a cycle in a linked list?" is a bad question because, if the candidate implements Floyd's algorithm on the whiteboard, the likely assumption is that they remembered it, not that they came up with it on the spot.

Exactly. Questions that have a super optimized answer that's probably non-intuitive and unlikely to be arrived at if you've only spent a few minutes exposed to the problem. These are basically puzzle questions in disguise.

In general I think there are two kinds of coding questions that are worth asking. Straightforward implementation based questions that should be solved basically as fast as the candidate can write, assuming they're familiar with the basic techniques. These are in the same vein as fizzbuzz and generally just give you a sense of the techniques the candidate has mastered (basic programming, bit-wise operations, recursion, etc.) The other kind are open ended questions that help show problem solving skills, knowledge of different algorithms and data structures, etc. These sorts of questions don't have the same variance as the secret puzzle questions. The amount of time to throw up a fizzbuzz implementation if you've seen the problem before should be about the same as if you haven't. And the same goes for open ended questions that are more about design, thinking, etc.

And of course you always want to factor in the problem of dealing with candidates who are nervous, in an unfamiliar and uncomfortable situation, and not operating at peak performance. You shouldn't expect production quality code for complex problems in those situations, you should be looking for code that gives you data.

In some ways, the problem is never the question, but how the results are evaluated.

I generally agree that "Aha" questions are bad, but if it's a common problem that people actually re-invent solutions to, it can still be a useful interview question. I personally avoid them, but see a few advantages:

1. If they're not aware of an existing algorithm, it's good to see what they come up with isn't terrible. It's insane the number of times I've seen unbounded time shuffle algorithms in production code. (Repeatedly pick a random element from src, linear scan of dst, and append to dst if not found.)

2. If they know a few famous algorithms, it's much more likely they're aware of the existence of lots of algorithms and are much more likely to Google for the pre-existing algorithm instead of making up something terrible on the spot.

3. A lot of these famous algorithms aren't as difficult to come up with as you'd think. When I first heard of the key schedule biases in RC-4, I thought about it for half an hour and came up with something identical to Fischer-Yates, using the unbalanced Feistel cipher at the core of MD5 (unfortunately, killing the speed advantages of RC4). Years later, when I heard there was a name for the algorithm, I checked Google to see if they had included the back-to-front optimization, and sure enough, what I had come up with was identical to Fischer-Yates.

in Lisp you use two pointers (a fast and a slow one) to detect a cycle in a linked list. For example http://clhs.lisp.se/Body/f_list_l.htm

Is this really a phenomenon that is exclusive to Bay Area companies though?

I don't about "exclusive" but the very first time a "data structures and algorithms" question ever appeared in an interview I had was in the Bay Area, after having spent 10+ years on the east coast. Prior to that interviews focused almost exclusively on design patterns (not just OO, but general architecture), project experience, and language specific questions where appropriate. I've been here a while now so I have no idea what the interview culture outside the Bay Area is like anymore.

This area has a high density of people who conflate academic computer science with software engineering, or who think the latter is some easily learned demi-skill to be looked down on, etc.

> conflate academic computer science with software engineering

Which is mind boggling. I took an introductory "software engineering" class in (a reasonably prestigious) university ~15 yrs ago which was ostensibly about learning how to use the right tool for the right job, and one of the assignments was to build a web application in C++!

Perhaps the intent of that assignment was to show that it wasn't the right tool, but that was certainly never communicated by the professor.

I didn't really learn any software engineering until I got my first job and had to build software, with a team, that people actually used.

Would modern c++ with a decent framework be that bad for web development? I imagine you'd have to do a bit more wiring due to the lack of reflection etc, but that isn't an insurmountable problem.

Edit - There a quite a few frameworks out there. This one seemed quite nice: https://github.com/ipkn/crow

It would usually be a wrong tool for all of these reasons:

1. There isn't a low-level performance bottleneck within most web-dev code. It's almost all occurring at levels slightly above that(disk access, network bandwidth, database queries, horizontal scaling). The stuff that needs to eke out another 50% in an inner loop through optimizing cache access or careful use of hardware parallelism tends to be a single algorithm or batch process that can be developed independently of the larger application.

2. For eliminating whole categories of errors, there is a bounty of options out there that can claim to improve on C++ through better tools, type systems, and compiler technologies. Even Java, as maligned as it is, can constitute a credible step forward.

3. Good C++ developers aren't that common. There are plenty of junior developers who are eager and ignorant of the potential dangers, though - they will make a mess in any environment, but they'll make a bigger one when given power tools. (This is the argument for Go, and w/r to the case of low-pass-filtering junior devs it definitely makes sense.)

Some counterpoints:

1. There are a number of reasons one might choose C++ that aren't related to low-level performance in almost any application. For a particular web application it may or may not be a good choice, but I wouldn't categorically reject it, even for a class project or assignment web app.

2. Any language or suite of them has whole categories of errors, deficiencies in tooling and other issues that can make it suitable or not in the hands of a given team. C++ has more or fewer of these than other languages depending on the context.

3. This seems to be hurling a pretty broad insult at many C++ developers, and "good" requires context.

Obviously this is a very late response to this thread, but I thought I'd add what I actually ended up building for this assignment.

The requirements were specifically to build a game, any game, and as long as it was playable (and your code was readable) you'd get an A.

So, annoyed as I was at the requirement that the backend be built in C++, I decided go above and beyond the requirements and built a single page Othello game, complete with a strong and fast AI (I happened to take this class much later in my studies than the standard curriculum called for, so I had already taken an AI class and had learned how to build a minimax tree with alpha beta pruning, though up until that point I'd only ever done it in Lisp).

So, by changing the actual requirements of the project, I actually made C++ a more appropriate choice of tools for this project and was able to build a very responsive single page Othello game with a strong AI capable of running pretty fast on the hardware we were tasked with using.

I was the only one who used Ajax to make it a single page app, and the only person to build an AI. Needless to say, I got the best grade in the class, but I suppose I had an unfair advantage.

> There are plenty of junior developers who are eager and ignorant of the potential dangers, though - they will make a mess in any environment, but they'll make a bigger one when given power tools.

I've often wondered about this. c++ has a tendency to fail fast and hard whereas higher level languages can lead to a false sense of security/understanding. Blowing your foot off isn't necessarily a bad thing.

one of the assignments was to build a web application in C++!

As an aside, we were doing this in the mid-late 90s (NSAPI) and we were running rings around Perl/CGI shops. Why? Because what took them a whole rack of machines took us a single box, and we simply skipped all the issues of syncing data, accessing a shared database with locking etc etc etc that they had to deal with.

Right tool for the job ;-)

see my (late) follow up comment: https://news.ycombinator.com/item?id=12559900

>>You must be able to mad-libs complete the paraphrase of recent CS textbooks, or you obviously never covered the topic.

Only recently a friend of mine narrated an interview tale. I don't exactly remember the precise question, but apparently he was asked to solve a problem in 30 mins(Two problems is what interviewer expected him to solve in an hour). One of such problem apparently he couldn't solve it in the time complexity the interviewer expected him to. Though he got some solution working in an hour.

He later on went and googled it and apparently the algorithm couldn't be solved unless you knew about Suffix Automata(http://codeforces.com/blog/entry/20861)

Long story short, these days apparently without everyday exposure competitive programming exercises(spending hours every day on sites like codeforces, SPOJ and hackerrank) there is no way you can clear interviews.

> Suffix Automata

Reminds me of the Aho-Corasick string-matching algorithm.

https://en.wikipedia.org/wiki/Aho–Corasick_algorithm

I'm always amused when I have a polar opposite experience to someone's virulent assertions, which is definitely the case here.

Edit: in a further comment, you assert an unspoken insult being communicated in a perfectly neutral sentence. I guess what I'm saying is I bet you bring quite a bit of the negativity you experience to your interactions.

Edit: in a further comment, you assert an unspoken insult being communicated in a perfectly neutral sentence.

It was entirely certain that he did not understand that he repeated the 2nd option I gave him. Furthermore, when I tried to correct him, he behaved as if I was lying to him.

I don't know what happened, because I wasn't there, but I do know that it's perfectly possible to communicate an unspoken insult in a perfectly neutral sentence.

I am not convinced that your assumption about his negativity is any more valid than his interpretation of his experience.

And I'd like to posit that you too may be incorrect about your assertion, as I have surely experienced a different interpretation albeit assumption of reality

I concur with you. People who have a super negative impression of SF nerds should re-consider their choice of nerds they are finding themselves around.

My own experiences in SF has been positive. I've found people are generally very excited about what they are doing in life, optimistic about the future and most importantly, willing to lend a hand. (This is in huge contrast to the cut throat image of the valley in the media; while individual startups and industries within tech may be cut throat, I wouldn't describe SF tech world as "generally cut throat")

One thing to keep in mind is SF has a fair share of folks who move here for their first job. These people are just entering the workforce and are maturing more, not less, each day. I've seen some pretty radical transformations of the same people over 1-3 years. A lot of the portrayal of the Valley in the media is of a fixed non-evolving mindset, which again, is the opposite of my experience.

> unspoken insult being communicated in a perfectly neutral sentence

I take it you're not familiar with the wonder that is Yes, Minister?

(More broadly, and to explain the joke for the benefit of HN, a large amount of British oblique humor and especially political and civil service culture relies on the art of the indirect insult.)

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