Interview:
Candidate claims being seasoned "senior".

Him: i don't know how the solve this
Me: you have to use binary search
Him: ahhaaa
Me: do you know binary search?
Him: yes
Me: can you please explain binary search?
Him: eghm, hmm, sorry I can't

I guess binary search is quite fundamental, but just poking at certain skills isn't always representative imo

@ScriptCoded he was bad in everything else as well. Point here is he lied that he knows it, and when I ask to explain, he couldn't.

I feel like this sort of thing doesn't come up for me, or perhaps I don't realise it when it does.

I focus more on design patterns than algorithms, maybe a bad thing. But I feel like you can be a senior with little memorised algorithm skills. Maybe not a senior skillset overall, but a senior level n the business sense. After all I've worked with 'seniors' that have fucked the whole project for lack of design.

Some people are seniors bc their companies kept them around

@bzq84 when was the last time you implemented an alg yourself? Be honest.

@DevLivesMatter it was not to implement it. It was about to explain how it works in own words. Even drawing conceptual model on paper would be sufficient.

Do you think there would be a high likelihood of a candidate needing to implement a binary search for the position? If no, then it’s a redundant question. Implementing search/sort algorithms is kinda niche these days, don’t expect every dev to know them like it’s common practice.

In most areas, you can go an absurdly long way with a negative value in algorithmic thinking and no knowledge about algorithms whatsoever.

If you aren't actually interested in understanding the algorithms, you mostly are totally fine just using what libs provide you.
Sure, you will not be able to solve problems of which not all parts have been solved by library authors before. But to be honest: Most devs are never gonna need to.

So yes, you can get to senior level without knowing shit about algos, not being able to explain anything to anyone and not being able to invent new algorithms.
Could even be a fantastic dev to have in your team...

Maybe he is really good at using libs and frameworks to implement business logic using the testdriven development approach.
Or maybe he has a ton of industry-specific business knowledge (maybe even an engineering background)...

But that indeed all doesn't matter if you really catched him lying.

Well yes not knowing binary search isn’t horrible if you spent years developing without touching it but the op did mention he sucked everywhere else as well

I don’t remember how binary search works. I didn’t even remembered binary search exists until I stumbled on this rant.

Last time I remembered how it works was last year due to those stupid recruitment questions.
I forgot it next day I got job cause it’s useless knowledge. Honestly I forgot everything I was learning to get next project.

Usually when I start new project and the code is already there I’m amazed by fact it works cause people bothered by binary search don’t know how to divide code into functions or use proper data structures. They’re implementing their stupid algorithms that have nothing todo with business requirements so I have to fix this shit and convince them that this is what the fucking business wants.

The business is amazed by the fact that I fixed something in one day that was unfixable before lol.

So yeah use your binary search and play smart jerk.

Binary search implementation? Ok then.
Counter question:
Have you ever had to actually implement it from scratch, instead of using a generic lib implementation for production use? If yes, then Why did you feel a need to waste time and resources on it?

Being senior means knowing how to use the standard tools to solve problems. You don't actually need to "know" how a low level "open a file descriptor", and "how write to it" actually works - and asking about it has the same validity as a binary search question....

You are all attacking the man as if he purposely, intentively and actively believes that algo questions are the be all end all.

The candidate in question applied as a 'SENIOR', even if you have been an ace web developer your entire life, it is important to understand the underlying principles of algorithms and data structures since these fundamentally add the notion of algorithmic efficiency to the process of building software. No, he is not expecting a candidate to use binary search or create different data structures, like a linked list from scratch on the applicant's every day job, but if I interview a senior and he says he knows what binary search is then he very DAMN well know how to explain it, else he is LYING and I do not want a lying ass mfker in my office, other than myself of course.

The problem is not how useful they are, which they are, don't know how thinking about the foundations of comp sci would be useless, but the problem is that the candidate lied.

@Oktokolo exactly, I am pretty sure he would have been open to having him on his team by looking at his development experience. Design patterns are more important to me than algos, but I still believe that it is important to know them, at the end of the day, like you said, if he lied then nothing really matters.

I was harsh cause binary search is junior question. Well sorry for that...

I always feel offended hearing question about algorithms or language behavior during interviews for senior+ positions.

That’s one of the most fucked up thing in this industry.

Senior for me always equals someone who can implement business values with their consequences.

@AleCx04
You are correct. He is not a SENIOR. He is MANAGMENT.

And the binary search question is valid in the context of the interview, and can be used to filter real devs from non devs.

OP here. @AleCx04 thank you. Exactly my point.

@vane the main task in the interview was different. To solve real problem, one should e.g. use binary search. Thus I asked candidate if he knows binary search, as a help, after he said he can't solve the original task.

@magicMirror there are exceptions to the rule. I am the senior developer in my department, I am also the manager. I don't know why this industry have put Business Administration holders in positions in which a senior and properly trained Software Engineer should be placed. But alas here we are

I'm with @bzq84 here. You can't pretend to be a senior dev and not be able to explain (not implement) something as basic as binary search. I mean, this thing is literally everywhere.

At least you should be honest and say "I do remember I learned it, but I can't remember the details, could you give me a hint and then I'm sure I can explain it in depth"

@AleCx04 Exactly.

I personally refrain from asking questions about specific algorithms and want the interviewee to guide that part to see what they would bring up/are knowledgable of.

But if they claim to know anything during the interview, even if it's the most useless shit, I want them to explain that thing.

I am not sure if mine is a good approach, it's probably because I'm used to liars around here. But when they aren't lying, what they bring up is something they are passionate about and then I feel it forms a great discussion.

But I just don't get those disagreeing with @bzq84. If the candidate is unable to answer truthfully about knowing something, that's a red flag for me.