[bandrami]

I have a question I usually ask which is "How would you convert a Julian yyyy-ddd date string to a military yyyy-mm-dd date string?" (I explain how a Julian date works if they aren't familiar with it.)

The answer that almost guarantees I'll hire you is "there's got to be a library function for that, so I look in the manual". Almost as good is somebody whiteboarding how they'd convert ddd to mm-dd (and then account for leap years, etc.)

I get a disturbing number of people who say things like "I would communicate with the person asking for this to see what they're really intending blah blah"

My favorite answer was on a phone interview where he just hung up and wouldn't answer when we called back.

[nkrisc]

> I get a disturbing number of people who say things like "I would communicate with the person asking for this to see what they're really intending blah blah"

Sounds like they know this question is a “gotcha” question but just misinterpreted which direction you were going with it.

Some will ask a question like this expecting you to treat it like a puzzle and outline how you’d solve it as-is; others ask it as a way to probe how you’ll deal with strange or misguided requests (the case you noted as disturbing); and others yet will ask it to see how you’d practically solve it (your intention).

Seems like a bad interview question without context regarding kind of answer you’re looking for.

[bandrami]

No, it's a pretty good interview question because it tells me if somebody's instinct is to reinvent the wheel or not. What I didn't expect was how many people couldn't say how a wheel even works.

[firmretention]

People are not generally answering interview questions based on instinct, but rather based on what they think the interviewer wants to hear to get the job. I would have interpreted this is as a leetcode style algo question and started by treating it as such, even though IRL my first instinct would be "get a lib that does it". Awful, awful strategy.

[bluGill]

It appears that either answer would be accepted, and so I'm fine with it. If it really is there is one correct answer then I'm against this. This feels like a problem where a good enough solution can be done in the time of an interview if you do it by hand (though if anyone knows about dates they will expect there is a lifetime of fixing special cases left if you don't use the library)

I prefer fizz-buzz as a question because it is obvious there isn't a library. It is also a problem you should be able to do in an interview. It has enough weirdness that there is no best answer, despite having several workable paths you could try.

[bandrami]

I mean, any answer is "accepted" in the sense that the whole point is to let me see how you think about solving simple problems. What has been distressing is seeing the number of applicants who can't even try, when it's the trying I want to see.

[bluGill]

It is shocking how often there is one acceptable correct answer and they don't care about the approach to solving problems only the score in a pass fail way.

[bandrami]

Nope, not remotely awful. I've made great hires from it, which is its point.

[vouwfietsman]

Its not. Any interview question where you are looking for a specific answer is already suspect, but especially if you don't properly provide context for the question in what you would expect, things become a shit show.

If you would ask someone to write a piece of code, and a part of the problem is this conversion, then you would be right to expect they reach for a library, but even if they don't you would be giving them the opportunity to explain themselves, and judge the explanation, not the answer. Also, if your test is "does this person reach for a library at the right time", you could do a lot less esoteric and confusing by just asking them to add 10 days to a date. If you just ask this one specific problem, it is likely they assume you are looking for them to demonstrate the skills involved in actually solving the problem, i.e. leetcode.

This is also why some people give you the blabla answer, because it is indeed very unlikely that someone needs to do this legitimately. This is because its a toy problem. Someone's professional reaction to the problem in isolation should indeed be: this is weird, I've never been asked something like this, what's up?

Finally, even though the question is terrible, I would still rate the "whatsup?" response higher than the "leapyear" response. I would want a developer to triple check that this problem needs solving, before they would solve it themselves.

Finally finally, if there's one answer to one question that, when answered trivially in a way literally taught in most basic programming courses (use the standard library / a third party library), makes them a "guaranteed hire", I also have significant doubts about the level of talent you are bringing in, as any experienced interviewer will tell you that qualified people will get important questions wrong, and unqualified people will get important questions right.

I understand that this reaction might be quite harsh, and I know better than anyone that its hard and time consuming to do good interviews, but please consider that you are rejecting people who may be very confused and sad by this way of rejection.

[nkrisc]

But that's why the context of the question is important. It's not clear from your comment, but I'd give a different answer if the question was strictly academic in nature (reinventing the wheel) or focused on practical work realities (use a library).

[inigyou]

Even using a library isn't that practical. It may be the zeitgeist in JavaScript but that doesn't mean it's actually a good idea. Nobody remembers left-pad? If you're writing Java or Python then checking if your date class can already do it is a good idea.

[bandrami]

I've managed to work in tech for 30 years without ever significantly coming into contact with javascript professionally. I hire Ada and C programmers for a stodgy defense contractor where we have to wear ties and it takes 6 months to get a new library approved; unicorns don't really thrive in this environment (or in Fairfax County in general).

[rightbyte]

> My favorite answer was on a phone interview where he just hung up and wouldn't answer when we called back.

Heh ... yeah well I wish I had it to do that.

However, you are asking gotcha questions.

[bandrami]

If "I want to see your instincts towards solving a problem" is a "gotcha" then we should just draw lots to hire people.

[rightbyte]

I unironically not as a joke think that rolling a dice after vetting candidate credentials is about as good as most recruiting policies or better. To much bias for players.

Like talk to the person abit to avoid obvious toxic people and then fact check the credentials.

So yeah draw lots. Guessing right on whether you want a practical response for the gotcha or for them to solve the puzzle adds no value to the process.