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in reply to At the risk of saying something stupid-but-obvious about Roman Numerals

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Re^2: At the risk of saying something stupid-but-obvious about Roman Numerals
by eyepopslikeamosquito (Archbishop) on May 12, 2014 at 20:20 UTC

    I would have expected to find such a presentation presenting a problem which actually requires a search of an intractably-large space ... and, since this one clearly doesn’t
    It does for a golfer. :-) The search is required to improve the previous shortest known Python solution by replacing the shortest known magic formula:
    10**(205558%ord(r)%7)%9995
    with a new one in this form:
    hash(r+"magicstrng")%1001
    which is one stroke shorter. This is explained in more detail in the introductory "Lookup Table vs Magic Formula" section of The 10**21 Problem (Part I).

    But it would be a lot more interesting if the most-efficient algorithm for solving the actual representative-problem were what is presented “in the least number of keystrokes.”
    The shortest algorithms for solving the Roman to Decimal conversion problem have already been presented in:

Re^2: At the risk of saying something stupid-but-obvious about Roman Numerals
by wjw (Priest) on May 12, 2014 at 20:29 UTC
    I too am doing the popcorn munching. I doubt I will ever be able to use what I am reading about. I don't work on things that are that involved. I do understand the curiousness of the choice.

    However, I recall that when I was working at Cray Research back in the 90's, they took a bunch of very expensive computing time to calculate pi out to some ridiculously huge number of decimal places. Set a world record in doing so at the time if I recall correctly. I also recall that we were in the middle of one of those crises (oil?, unemployment? outsourcing?) and thinking that the very expensive compute time could have been spent on one or another of those intractable problems. I don't know what was learned from the exercise in pi, I presume something(perhaps mistakenly). I figure that in this case, the subject-matter is of interest to someone, and they find it challenging. Good for them. I am learning along the way, and ain't gonna look the gift-horse in the mouth... :-)

    ...the majority is always wrong, and always the last to know about it...
    Insanity: Doing the same thing over and over again and expecting different results...

      Funny that you should mention Pi.   When I worked at Amdahl, back in the day, a program to calculate digits-of-pi was apparently one of their burn-in tests.   Or something like that.   I seem to vaguely recall them getting some press at one time about the number of digits they had helped calculate.

      No horse-evaluations here, either.