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Comment by sillysaurus3 | Hacker News Reader

If you're 10 or 15 years out of college, you're way less likely to be able to answer the standard "Implement a red-black tree on a whiteboard" type question. Recent grads have a tremendous advantage here.

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There are very few people out of college who can implement a red-black tree on a whiteboard. Heck even those who just finished the data structure course while still in university. Even with the algorithm book open in front of them I doubt most developers can have anything working and good implemented in one hour.

If you've spent the last 10-15 years writing code every day you can review your data structures course book before an interview and do better than most fresh graduates.

Ageism is real I know lots of people >40 and >50 who hold good jobs and are also able to get good jobs if they end up being laid off for some reason. But then there are also people in their twenties who have a difficult time getting a good job for whatever reason. There are lots of factors.

"Implement a red-black tree on a whiteboard" is code for "we don't know how to interview, so we ask about stuff that the hiree will never do". I'm not so sure the "advantage" is actually an advantage.

Which means Google doesn't know how to interview.

Norvig said* that their tracking of peoples performance shows that people who would normally be filtered out by their standard tests, but still were hired due to someone fighting for them do constantly better than those who do well in their interviews. So yes, Google actually doesn't know how to interview.

* As far as I remember it was in Coders at Work (very good book btw)

It just means that the people who were hired outside the standard process were extremely talented and were worth fighting for. It does mean anything about Google's interview process because it is geared towards an application from your average Joe from the street.

Wouldn't that be an argument from authority?

Yeah, it's very possible that Google doesn't know how to interview. I don't think it's a solved problem anywhere in the industry -- teams just do what seems to work for them, with lots of false positives and negatives.

I'd agree with that. If it takes 10 interviews for a company to properly assess someone, the problem is most definitely with the company.

To be fair, Google, Netflix, FB, Amazon, etc are some of the companies on a very short list of places where you would actually need to have an in depth knowledge of this type of stuff to do your job well. If your job is scaling or optimization at Google, yes you should definitely know this stuff. If your job is building the latest CRUD app in Xamarin, you probably don't need to know how to implement your own bubble sort in pseudo code (without access to any resources, at that).

Well, they don't. They hire people who make Glass, Wave, Buzz and all the other projects they've had to cancel because their staff are so out of sync with the real world.

They did make the "why are manhole covers round" type of questions popular a few years back. Then admitted later that it had no correlation with on the job performance.

Classic argument from authority. Big, successful entities can do dumb shit too.

Google might be one of the few companies in the world where this kind of knowledge is relevant for the work you do.

but it knows how to select, and that's way more important.

We are talking about real jobs now, the ones with real coding interviews because they pay real money and come with stability and opportunity within an exciting company-- just to clarify. DHH said something about this recently and how he could not do a bubble sort if his life depended on it or something to that effect. So, yeah. You're right. And these respected people need to start doing something about this gated community of tech. The thing-- well, one of the many things-- people need to start getting honest about is how we interview and what we consider "skill" or "merit" and if that thing should be the thing we select for. If the interview system is all about how well you can memorize "Cracking the Coding Interview" and the like and then how well you can act like you are then "thinking it through at sight, never before having seen it" (which is exactly what it's about now in this age of bootcamp prep for bootcamp prep for bootcamp), then isn't the interview system selecting for a very particular type of person? I'd say that person has a lot of time on their hands and a desperate need to get a job in programming. That person somehow bought that time with loans they are scared to death they will never be able to pay back (they probably won't) because they are career changers, or they are young or youngish- still parentally funded--- or just still parentally funded. Or their spouse or partner has $$ work and they can afford to take the time to practice these things to be competitive. I'm sure there is an exception of one woman, against all odds here, but I have not yet met her. Please, give her a shout out! So, basically this tech interview process filters for young people with money and leisure time to practice the "skill" of programming until they can whiteboard like Marlon Brando. Not to ding algorithms- they are cool and all, but you see what I'm saying. We are trying to convince ourselves that we are still pre post-labor. And the cracks are showing when labor is now a gated community that likes to hire Ivy League Grads and likes to keep out people of color, women, people over 35,etc...and then likes to also get itself into the new - well, I won't give it a name... let's call it the H1B program for short.

I don't like this question for an interview. But I have also seen and received questions with a larger scope that require working together, asking questions, etc.

Had the classic 'what happens when you type a URL in the address bar of a browser' last week. I don't think any recent grad could compete with the things I even half remember on that one. It used to annoy me as a superfluous question, but realised it's a good way of showing you know what's actually going on in the machine, your understanding of middleware, GPUs, caches, networking etc etc.

The easy answer to that is: I have it configured to search through a list of my history, otherwise nothing happens. You have to press enter for it to search for it :_)

Not really.

You can still go on about how there is a keydown/keyup event, DNS lookups, safe-browsing lookups (Google, Firefox), cache hits or not, GPU redraws, etc etc.

It's a question for asking how much you know about which bits are flipped when anything happens. You can literally pick any bit of the pipeline and riff about it. Assuming that is you know about them.

I know, I was deliberately giving a sarcastic answer to show that the example should be better worded.

Ah, gotya!

Just memorize a few variations. Not that hard. And, full disclosure, I've only been asked that once - I played dumb, just because I'm contrarian like that - and the interviewer thought I did a fantastic job of "thinking through the problem."

Recent grads may have an advantage in answering such questions, but that doesn't mean they have an advantage on the job. Jobs that require you to be able to implement a red-black tree are extremely rare. Experience should count for more.

It should yes, but to get the job and show the advantages of experience you must first pass the inane filter, that's the issue.

An easy fix to this is to not apply for jobs where you get these ridiculous questions despite the 15+ years of experience on your resume. Unless you're going to be implementing your own data structures and/or algorithms, of course.

Yup, that's an easy fix. Where's the unemployment line again?

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