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Comment by jchonphoenix | Hacker News Reader

I disagree. If you know what a binary search tree or linked list is, you should be able to code them. If you can't do something this simple, how can you be expected to actually solve a problem that you can't just look up the answer too?

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Well I know that I've solved a few problems in my time: like developing a multi-threaded distributed object-oriented control system, implementing a JPEG2000 encoder, a convolutional neural net, as well as solving a number of debugging problems that escaped my colleagues.

I also know I failed miserably at a trivial coding task in an interview.

So I don't know. If I'm the only one who has that kind of problem, maybe my brain works differently from other people's.

How trivial? What was the task, then? And what where the conditions? Were you required to remember some nitty details? In an interview, you can fail in almost anything, depending on how nervous you are.

The problem was: given the following prototype implement the function

  void move( char** colNames, int toColumn, int fromColumn );

The function should move the column name at index fromColumn to the position toColumn. (It does not swap the columns.)

Now I just spent 43 min implementing this with a compiler and some trial and error.

During the interview I was expected to do it with pen and paper.

Now my IQ is above the 99th percentile but apparently there are people who can do this sort of thing in their head without errors and that's what some interviewers appear to be looking for. That's why this post hit home for me, though personally I probably wouldn't have had much trouble with linked lists.

I'll agree with this on one condition: don't hold syntax errors against me. I interviewed for a position about eight months ago. I was rusty with my C (had been doing more java and python around that time), and put "int i = 0" in a for loop on a white board and seemingly had it counted against me. This kind of thing, along with things like missed semicolons, should be ignored by interviewers. Not only is it a simple fix, it also says nothing about the logic in the code.

That's even legal syntax in C99.

Unless I've needed a specific language, like SQL for example, anytime I've asked a candidate to code on the whiteboard pseudocode has always been fine.

What makes you think it was held against you? Most programmers can be kind of OCD about code and would want to point out that kind of error, whether they thought it was relevant to your abilities or not.

Assuming you mean for (int i = 0; ; ) {} that is legal syntax. Perhaps I'm dull, but what is the error?

I think the point was that in C(89) you need to declare all variables at the beginning of the scope block.

Can't code one on a whiteboard != can't code one

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