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Comment by sergiotapia | Hacker News Reader

Concerning that they ask you computer science questions when you will be working on the front end.

What if you were to ask CSS and Javascript questions to a DBA? Do you see how absolutely ridiculous that sounds?

More ridiculous than asking CS questions of a front end dev. I'm a self-taught front-end dev who has flunked numerous interviews because of a lack of CS degree and being able to get through the sorting algorithm questions. I then went home and have spent lots and lots of time teaching myself those fundamentals, if only to interview better. Those fundamentals have made me a vastly better front end dev, able to efficiently solve problems I wouldn't have been able to solve a year ago.

I have had the exact same experience with the author of the article regarding a total absence of actual front-end related questions, though. Not sure how to feel about not getting those gigs.

Can you give some examples of which algorithm have been the most relevant/helpful?

I was recently asked a "making change" question [1] in a front-end interview, and once I finally understood it, it really really helped my comprehension of how to properly dissect tree-recursion-branching problems. Here's the code, https://gist.github.com/derek/8073844.

Another one that popped up in an interview was sub-string matching, which I bombed, but after learning Boyer-Moore-Horspool I have a much greater understanding of efficiently designing algorithms. It is the algorithm some browsers use under the hood for String.prototype.indexOf [3]. Here's that code, https://gist.github.com/derek/8035740.

[1] http://en.wikipedia.org/wiki/Change-making_problem

[2] http://en.wikipedia.org/wiki/Boyer%E2%80%93Moore%E2%80%93Hor...

[3] http://javascriptrules.com/2009/08/12/string-searching-algor...

His silence is highly amusing to me. :)

Your condescension is highly distasteful to me.

Who was he talking about? Me? If so, I upvoted the reply, what more do I need to do?

Well, if the developer is creating custom components, or simply manipulating data, then they need to know some good algorithms (at least know they exist and what to look for). Like when creating a table that needs to sort the rows. If you don't know how to do this, then you could have a really bad 0(N2) algorithm that just kills the browser with even a small list of items. Or, if you need write an algorithm to pack a bunch of rectangles on a screen (like a day calendar) so they don't overlap.

Yes, there are computer science topics that apply to the front end. If you are writing Javascript (not just marking up stuff and applying CSS), then you want to know how this works. This isn't the 90's simple form submission javascript. It's a completely different world in the browser now.

Well, given the new trend of fat JS clients, if you have no clue about algorithmic complexity, you can fairly easily end with a very sluggish application, even under Chrome.

I don't expect from a front-end engineer to just drop random jQuery plugins on top of each others.

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