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Comment by gnulinux | Hacker News Reader

Honestly I don't understand this mass hysteria about programming questions. If you go over any algorithms textbook you'll see all the algorithms that will ever be asked by any company in the world, ever. One time I was interviewing for Google, in the very last phase, and apparently this was one of the hardest question they ask. The question was just asking me to implement MaxFlow algorithm (of course not directly). I don't think there is any textbook in the world that won't go over maximum flow. Besides, usually they don't need you to solve the problem in entirety but to show them you can make some progress on the problem.

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Because the only people that can really make it, without being lucky, are the ones that just finished their CS degree.

I had my "Algorithms & Data Structures" somewhere around 1996.

How often do you thing I am implementing AVL and B-Trees on typical enterprise applications?

MaxFlow? I had to google for what it is all about.

This...ain’t it chief.

You won’t pass HC if you don’t at minimum solve the problem at all. And max flow is a nontrivial algorithm, more so than any of the ones I’ve ever known people to get.

You have to have pretty amazing natural talent to be able to get it cold without much studying.

I think it’s a shame that there doesn’t seem to be a middle ground opinion between the elitist “you mean you don’t know about Ford Fulkerson without studying?” and the anti intellectual “all coding interviews are just luck and not a good signal”...

Boom, well said. What I have seen is that most of these cries are from the majority without CS background or those that didn't take their schooling serious. I have seen enough people without CS background who don't care about programming questions because they have taken the time to study their algorithm & data structures. As much crap as the FANG get for their interviews, there's a reason they are the top companies. What they're doing is obviously working.

I wonder if you realize that in many countries, computer science was a very obscure academic path until very recently. Most schools in France wouldn't offer it until very late for example.

The older, more experienced people at these companies you cite are the ones less likely to have CS degrees, which only became a staple recently. The companies now ask for one because it's an easy mass fizzbuzz filter. It doesn't help them get the best engineers, it helps them not get the worst ones. They have the volume to make up for it.

Saying what they're doing shows ignorance as to why it's working.

Sure, there may be a correlation between a candidate's ability to answer every kind of algorithm & data structure problem across multiple respected CS textbooks and their performance at any one of these companies, but what of the many other confounding variables? What of the benefits, day-to-day perks, prestige, future open doors, workplace culture, or scale of the products they launch? Do those kinds of variables not also greatly impact the ability to attract and select top talent?

> If you go over any algorithms textbook you'll see all the algorithms that will ever be asked by any company in the world, ever.

So where’s the value as a primary interview technique? Is selecting for people who can read a textbook that helpful?

I imagine it selects for people who want the job at a FAANG company so badly that they spend a lot of time reading algo textbooks and grinding Leetcode. I guess this is also a proxy for other character traits, like grit, pattern recognition, learning from mistakes, and so on.

Nope. The main determinants of effectiveness are 2 things:

1) general intelligence

2) conscientiousness (how much effort you put into what you do)

Don't you think asking applied textbook problems is an excellent way to test for both at the same time ?

If you are smart, then what is the problem with going through an algorithm textbook, listening to Youtube explanations when you can't follow and just spending your evenings for 3 weeks or so. Frankly, if you get to chapter 5 out of 20, you've probably seen what you will be asked, so you could easily stop after one week and still easily pass the interview bar.

And if that's too much effort, why should they assume you'll put in effort once you get hired ? They'll be expecting more than one week's worth of effort from you.

Furthermore, Google actually tracks how well it's questions work, how the resulting hires perform. If there really was no correlation there, they'd have changed it (also they've documented it in Laszlo's book, well at this point books)

I bet it would measure even better if they told you a week beforehand that the question would involve some obscure, not super easy but not super difficult algorithm, but one that they can reasonably assume you've never seen before and then asked you to apply it on the interview.

conscientiousness is more complex than that. You have to understand what positive benefits manifest in what scenario for every given level of conscientiousness.

I'm very low-c and that means I have a proclivity to procrastinate and a tendency to not be able to stick with things very long term of my own volition. This doesn't make things impossible to do for me as I even managed to become fluent in Japanese which was a tortuous multi-year effort. Suffice to say higher conscientious would be nice, but it means I have a tendency to also not feel the need to follow all the rules all of the time and this results in my sometimes taking a contrarian or unorthodox approach and sometimes this has a massive and positive benefit. It also means I'm constantly forgetting to log my time sheets and take out the rubbish and things like that piss off my boss and my wife and this is generally considered a problem but my boss and my wife also love me because I do things they don't see other people doing and im considered unconventional but in a very good way.

Everything is a trade-off. It's not like all high conscientiousness people is the right mix of people to have.

I mean, Computer Science is practiced at Google. Shooting from the hip and excusing it as craftsmanship is generally frowned upon.

They're looking for a repeatable, fair baseline cut for basic competency and motivation, and "has this person ever read a compsci textbook" is a fair proxy for that.

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