I had an interview recently where the interviewer asked me, and I quote, "Please solve this using whatever language/editor/tools you're comfortable with and what you'd use in your day-to-day work"
So I pull out trusty old Ruby + RubyMine, and the question (I don't remember what it was specifically, but it was some sort of array manipulation type of thing) was trivially solvable with some Ruby STD lib method. Apparently he wasn't satisfied with the answer despite his prior instructions, and me not knowing what the actual method code is was reason enough to disqualify me from the job, which I found baffling.
I got into a bit of a heated discussion that, if I were solving a problem at work, there's a 99% chance I'd just reach for this method that Ruby itself comes with, because why the fuck would I try be a smartass and reinvent stuff here? And if for whatever insane reason I did indeed need a bespoke solution, I'd just poke around the source code and extrapolate from there, which he still didn't consider a good answer.
I've had this happen to me in an interview before, from the other side.
I laughed that I had given them such an easy problem for their chosen language, then said "ok, pretend you went back in time and you're the person writing that function for the std lib" and so they did.
It probably wasn't as optimized as the actual stdlib function but it was good enough for the interview.
I gotta say if someone got heated with me about that request I'd end the interview early and not give them the job too.
The point isn't just providing a solution it's demonstrating that you can work through a simple problem. If you get heated about that during an interview then I don't get any info about your ability to work through problems, and I do get the impression that you're short tempered when asked to do things you don't care about.
Not OP but I dont think they got heated because they were asked to reason/invent stdlib function, it seems they got heated because they got disqualified for using stdlib function without knowing the exact algo the function uses beforehand.
So I pull out trusty old Ruby + RubyMine, and the question (I don't remember what it was specifically, but it was some sort of array manipulation type of thing) was trivially solvable with some Ruby STD lib method. Apparently he wasn't satisfied with the answer despite his prior instructions, and me not knowing what the actual method code is was reason enough to disqualify me from the job, which I found baffling.
I got into a bit of a heated discussion that, if I were solving a problem at work, there's a 99% chance I'd just reach for this method that Ruby itself comes with, because why the fuck would I try be a smartass and reinvent stuff here? And if for whatever insane reason I did indeed need a bespoke solution, I'd just poke around the source code and extrapolate from there, which he still didn't consider a good answer.
These interviewers drive me insane sometimes...