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in reply to Homework Golf

35 (OR 46 depending upon which of the scoring method used in this thread you favour):

#23456789_123456789_123456789_123456789_123456 # 123456789_123456789_123456789_12345 perl -nlE"unpack('%c*',$_&chr(31)x30)-65||say" words.txt

On *nix, it can be 1 shorter (correct nested 's; thanks choroba):

#23456789_123456789_123456789_123456789_12345 # 123456789_123456789_123456789_1234 perl -nlE'unpack("%c*",$_&"\x1f"x30)-65||say' words.txt

And one shorter still:

#23456789_123456789_123456789_123456789_12345 # 123456789_123456789_123456789_1234 perl -nlE'unpack("%c*",$_&"\c_"x30)-65||say' words.txt

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

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Re^2: Homework Golf (35)
by eyepopslikeamosquito (Bishop) on Dec 05, 2013 at 09:38 UTC

    On *nix ... one shorter still:
    #23456789_123456789_123456789_123456789_1234 perl -nlE'unpack("%c*",$_&"\c_"x30)-65||say' words.txt
    Two more strokes can be shaved I believe (untested, no Unix box available right now):
    #23456789_123456789_123456789_123456789_12 perl -nlE'65^unpack"%c*",$_&~"`"x30or say' words.txt
    Update: an alternative using v31:
    #23456789_123456789_123456789_123456789_12 perl -nlE'65^unpack"%c*",$_&v31 x30or say' words.txt

      I (breifly) looked for a replacement for "\c_", but I was trying to xor two bareword chars together to produce chr(31). I found several pairs that worked, but then as ^ has lower precedence than x, I couldn't extend the string cos if you bracket the expression, x produces a list not a string :(. Didn't think of &~'`'. Or vstrings:( )

      Also couldn't see how to ditch the unpack parens.

      As neither of the strings needs escape processing (unlike "\c_"), you can switch the "s <-> 's and that works on windows also:

      C:\test>perl -nlE"65^unpack'%c*',$_&~'`'x30or say" words.txt | wc -l 1279

      With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.
      There’s a third alternative using uc :
      #23456789_123456789_123456789_123456789_12 perl -nlE'65^unpack"%c*","?"x30&uc or say'
      Those spaces around or are annoying... Let's use something else to express conditionnal printing. With -p, x= does the job:
      #23456789_123456789_123456789_123456789_1 perl -ple'$_ x=65==unpack"%c*","?"x30&uc'
      While we're looking at those switches... Why the -l? Removing it and adding ord("\n") (10) to the target (65) shaves another stroke:
      #23456789_123456789_123456789_123456789_ perl -pe'$_ x=75=~unpack"%c*","?"x30&uc'
      There's a much shorter solution using a 6-bit checksum. The problem is that it comes up with a few false positives (words whose value is 1, 129, 193...):
      #23456789_123456789_123456789_1234 perl -ple'$_ x=1==unpack"%6c*",uc' perl -pe'$_ x=11==unpack"%6c*",uc'
      Using a 5-bit checksum removes the need for uc, but brings even more false positives:
      #23456789_123456789_123456789_1 perl -ple'$_ x=1==unpack"%5c*"' perl -pe'$_ x=11==unpack"%5c*"' perl -nlE'1^unpack"%5c*"or say' perl -nE'11^unpack"%5c*"or say'

        I'm pretty sure we have a winner here, at least in the perl5 division. Congrats for making me go look up x= ("Get outta here, that's legal? So it is!") and for the brilliant insight that lets you shave off the -l. +10 internets to Grimy!

Re^2: Homework Golf (35)
by McD (Chaplain) on Dec 05, 2013 at 02:09 UTC

    Wow, I love this.

    $_&"\c_"x30

    ...is about as close to executable line noise as I've seen in a long, long time. Bravo!

    If I'm smart, I'll borrow all these tricks, next time I come up with a golf idea. :-)