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    Debuggers: James Hague c debuggers.co
    khamidou avatar via khamidou 4 years ago | cached | 5 comments

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    Sophistifunk avatar Sophistifunk 4 years ago | link

    Am I the only one who thinks the “correct” code is awful? I’d much rather just see an if statement added to the first padding code. Bit twiddling should be reserved for inner-inner-inner-loop optimisations. They’re all about “how” with none of the “why”

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      animatronic avatar animatronic 4 years ago | link

      Yeah, I looked at the “fixed” code and am like, “oh man, I have to get out a REPL an start seeing how this works”

      def pad(amount,size):
    q, r = divmod(amount,size)
    if r == 0:
        padded = q * size
    else:
        padded = (q + 1) * size

    assert padded % size == 0, padded
    return padded

      or this

      /*
   pad to next whole 2048 up
*/
int obvious_pad(int size) {
    int q = size / 2048;
    int r = size % 2048;
    return (q + (r != 0 ? 1 : 0)) * 2048;
}
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        pilkch avatar pilkch 4 years ago | link

        I came up with your second solution too :)
        return ((size / 2048) + (((size % 2048) != 0) ? 1 : 0)) * 2048;

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        zem avatar zem 4 years ago | link

        i’m guessing once you’ve done enough bit twiddling, that just reads as a mod operation to you

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        pilkch avatar pilkch 4 years ago | link

        Unit testing. I know, this was the 90’s, unit testing didn’t exist yet. I’m sure everyone would write a unit test for this nowadays. Right?