Sometimes there's no time to google, and you want to be talking to someone while you're doing it, as a sanity check. https://dealbook.nytimes.com/2012/08/02/knight-capital-says-... $10M/minute is an extreme case, but these things happen on a smaller scale all the time. I'm not saying this is the justification for coding interviews, just saying that it happens, and the ability to code something up quickly that also works correctly without having time to test it sometimes saves the day. I do think coding interviews that people are complaining about are good, and getting in shape to do well in them is good for you. You can tell it's good for you just by the amount of complaining people are doing :)

>Sometimes there's no time to google

What do you mean no time to Google? You're never going to be able to remember everything. Sure the ideal situation is that you're fixing a bug where you happen to know the exact syntax for every piece of every library you need.

But in the very likely situation where you don't, of course you have time to google.

>and the ability to code something up quickly that also works correctly without having time to test it sometimes saves the day.

Often becuase the company has optimized the hiring process for people who are good at doing this vs. people who are good at designing maintainable, durable systems.

If 30 minute, million dollar fixes is a frequent enough occurrence to make aptitude at them the primary or even a major factor in your hiring decision, you have done something horribly wrong.

>I do think coding interviews that people are complaining about are good, and getting in shape to do well in them is good for you.

Having hired people using many different techniques, I think that these types of interviews are only a bit better than random chance. They are a separate skill from 99% of daily programming work, and they are gameable. I also think they are nothing more than a fad caused by people cargo culting Google.

Not a single other technical discipline widley uses this kind of stage performance based interview process. Not one.

>and you want to be talking to someone while you're doing it, as a sanity check.

That makes zero sense. Sure sometimes it helps to talk through a problem if you're working with someone who is also trying to solve the problem with you, and you might want to explain a fix after you solve the problem but before you push as a sanity check.

But if it's a hard problem you can kick rocks if you expect me to explain what I'm thinking about while I'm concentrating on solving it--while you're watching over my shoulder, and are not actively engaged in helping me solve the problem. You're just slowing me down.

Many problems have solutions that were worthy of publication and took a lot longer than 30 minutes for very smart people to solve. So if you don't already know the answer or the answer to a very similar problem then yes objectively they are hard problems.

But you are supposed to know the algorithms and approaches that apply to the problem, that's the whole point. It took humanity tens of thousands of years to come up with the first script, but nobody wants you to invent the English alphabet in an interview, you're expected to know it.

I also can't remember ever being asked to solve a problem whose solution would have merited publication in my lifetime, and I was born around the same time Unix was.

There's a difference between knowing which class of algorithms to use or even which specific algorithm to lookup in a given situation and knowing exactly how to implement the specific pet algorithm of an engineer on a power trip without using reference materials. This kind of adversarial process is nothing more than a hazing ritual. Other industries think we're insane, and the vast majority of companies that do this style of interview just do it because they want to do what Google does not because they have any evidence it works.

>I also can't remember ever being asked to solve a problem whose solution would have merited publication in my lifetime, and I was born around the same time Unix was.

We've had different experiences then. I've definitely had to implement algorithms designed after 1971.

Software is very different from any other type of engineering I can think of, so I'm not surprised that the interviewing processes would be different. Two different aeronautical engineers for example may come up with two different solutions, but I don't think the better one would be better by a factor of ten, let alone something like a million which is common with software. If any aeronautical engineers read this I'd like to be corrected if I'm wrong.

I agree that for GUI work you probably don't need this, but for a back end position I would like a person for whom this kind of interview isn't a big deal to prepare for.

I'm curious to hear what the post 1971 algorithms in question are.

Wow you are really invested in the current interview process. I've never met anyone who defended it quite so vigorously.

Any engineering disciplines that deal with designing processes are very similar to software engineering. It's nowhere special enough to demand a completely unique hiring process.

Even if it were, I'd like to see some hard data to support the current interview best practices.

>I'm curious to hear what the post 1971 algorithms in question are.

Off the top of my head: You've had a question with Red-black trees? B-trees? Quad-trees and oct-trees?

There is no way you were asked to implement any of those in an interview.

For quad-trees and oct-trees--they are fairly common in gaming and not a particularly time consuming to implement.

For Red-Black and B-Trees, I've never heard of anyone being asked to implement the entire thing from scratch, but significant portions sure. Also explaining the implementation of significant portions.

Here's a similar post from 2015 by tptacek

>You're a 55-year old engineer who graduated from school in '81. You're being interviewed by a 24-year old engineer who graduated 2 years ago. You're asked, in an "algorithm interview", to explain some detail of the implementation of an AVL tree.

>In reality, despite the fact that they're covered in CS courses, virtually nobody uses AVL trees in industry. In fact, people barely use balanced binary trees at all, and when they do, they use red-black trees, and they use someone else's implementation, because they're a bear to debug.

>The 24-year old has an advantage with this question because they were recently taught about, and perhaps had to do exercises/homework/tests based on, AVL trees.

>That this happens is stupid, because it's very unlikely that conversance with AVL trees is going to make much of a difference to your on-the-job performance. Almost all the narratives you can come up with about this involve reading tea leaves and are shot down easily by better selection/hiring/interviewing techniques that answer questions more directly.

>This line of questioning can go too far; I don't, for instance, think knowing the big-O characteristics of an AVL tree is unreasonable (it's a balanced binary tree, and you should have the complexity of operations on those in resident set throughout your career).

Here's another coment from tptacek in the same thread. If you don't know who he is--you definitely want to hire him if you can. Him failing out of your hiring process would be a travesty.

>I was asked to do Bellman-Ford. I bombed that question, and was so shaken that I bombed the rest of the interview as well.

>The irony was, I'd just spent the preceding 2 years writing multicast link-state routing code. I could have coded a decent C++ Bellman-Ford in a couple hours, but couldn't pull it out of my head on the spot in an interview without babbling. (I tried to dodge by describing link-state LSP forwarding and then Djikstra, but wasn't given credit for knowing the more sophisticated algorithm).

>Algorithm interviews suck. We should stop doing them entirely.

Those are exceptions, if it was common to get these kinds of questions I would have gotten at least one like that at one of the many interviews I've been in. Getting rid of coding interviews won't stop some interviewers from being jerks. I much prefer being rejected for bombing a coding interview, than killing it and then getting rejected because of the behavioral interview, where someone 20 years younger than me acts like they can figure me out by asking me a bunch of silly questions.

First you deny the experience then when presented with evidence--the types of interviews people complain about are just rare.

>Getting rid of coding interviews won't stop some interviewers from being jerks. I much prefer being rejected for bombing a coding interview, than killing it and then getting rejected because of the behavioral interview

The same thing applies to your point. Coding interviews don't replace those issues they just add another hoop. What do you think behavioral questions, lunch interviews, and culture fit are?

>where someone 20 years younger than me acts like they can figure me out by asking me a bunch of silly questions.

Based on what I've observed this is what currently happens. 99% of companies have a terrible process for developing questions and evaluating responses.

And programming is pretty much the only field where it's the norm to be interviewed by someone much younger than you.

Here's the difference - when shit hits the fan everyone in the room wants to solve the problem and they are actively helping each other. Technical interview is completely different.

We conduct it as a working session. Our primary goals are to determine ability to reason about problems, apply the proper technique (not syntax), the ability to communicate with us about what they are doing clearly and to get a sense of how they work during the planning phase of a project. We are looking for a connection with the prospect more than a complete technical solution.

Worth saying, sometimes there’s nothing to google, or googling wouldn’t yield a significant answer - perhaps the issue lies in some module of fairly home grown code.

Sure that happens, but you probably have access to internal documentation, a compiler, a REPL--something.

The issue with not being able to Google isn't Google specifically, it's the lack of all the tools you use to solve real problems.

Google, or any other reference, is the hard drive, and the skill you have in your noggin is the cache. You wouldn't want to buy a machine that's all hard drive and no cache.

That analogy isn't a refutation of anything.