5 comments

  • nk_kolja 6 days ago
    I found a bug in Algorithm D, the long division algorithm in Knuth's "The Art of Computer Programming". It was discussed on HN a couple of times https://news.ycombinator.com/item?id=26562819 as well as on other websites. I sent a letter to Knuth and received a check and an annotated reply. The updated Theorem B, which was unchanged since 1969 is now dated 2026.

    While searching for vulnerable implementations I also found a "bug" in llvm, so I expanded a bit on that too.

    • jason_s 1 day ago
      Congratulations! Wow, you got a legendary $2.56 check....
      • WillAdams 1 hour ago
        Unfortunately, one no longer gets physical checks, instead, one gets an account in The Bank of the Island of San Seriffe:

        https://www-cs-faculty.stanford.edu/~knuth/boss.html

        (unfortunately, I have yet to find another typo since getting my $2.88 for _Digital Typography_)

        • malisper 1 hour ago
          You still get a physical piece of paper that looks like a check; it's just not a valid check.
          • nk_kolja 49 minutes ago
            It can still be cashed in, though not in any bank, you need to contact Knuth beforehand.

            For me it will stay framed on the wall.

            • WillAdams 22 minutes ago
              I wonder if one can do the reverse? Turn in a physical check and get an account?
      • warmwaffles 1 hour ago
        Hopefully framed it and put it on the wall.
  • globular-toast 36 minutes ago
    > "I'm especially glad to have this correction, because I think the readers of TAOCP Vol 2 look at Algorithm 4.3.1 D more than any other algorithm!"

    If you look at the fore edge of my copy of vol 2 will see a noticeably grubby line. Open the book at that page and you do indeed arrive at Algorithm D!

    I've implemented multiple-precision arithmetic at least a couple of times. I'm tempted to dig up an old project I haven't touched for over a decade and make the correction...

  • ginko 1 hour ago
    The typesetting of this looks very broken on firefox with extreme gaps between lines of text. Seems to render fine on chromium.
    • Retr0id 1 hour ago
      It renders fine for me, but I've also had the "extreme gaps between lines" thing happen before on Firefox, and in my case it was caused by a bad font fallback - I forget the precise details but I think it had something to do with having Arabic fonts installed, which were erroneously taking preference for certain non-arabic glyphs. (Check the Fonts tab in dev tools)
    • nk_kolja 45 minutes ago
      Thank you for letting me now, but I cannot replicate the issue on Firefox. There are some issues with math and the animations not breaking on mobile, which I am working on repairing.

      EDIT: I have added a different fallback font so it should work on your Firefox now.

    • metalliqaz 1 hour ago
      I use firefox and it renders approximately the same as Chrome for me.

      Assuming OP didn't patch something, you may have a misbehaving extension.