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in reply to Golf for unique digits

C:\test>perl -nlE"s[(.)(?=.*?\1)][]g;say length;"
1987
4
2013
4
2113
3
122398723456321467891356178653534
9
1111111111111111
1
121212121212121212121212
2

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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: Golf for unique digits (17)
by tye (Sage) on Jan 09, 2013 at 18:42 UTC
[reply]
[d/l]

      This seems to work just as well? 

      perl -nlE"say s/(.)(?!.*\1)//g"

      [download]
      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.
[reply]
[d/l]

      tye++ ... but I'm stuck to understand how it works?

      According to perlop:

      Searches a string for a pattern, and if found, replaces that pattern with the replacement text and returns the number of substitutions made.

      How does the number of substitutions made equate to the number of characters left after the substitutions?

      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.
[reply]
        >How does the number of substitutions made equate to the number of characters left after the substitutions?

        (?!..) = not followed by!

        every cipher is exactly once the last of it's kind! =)

        Cheers Rolf

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[d/l]
Re^2: Golf for unique digits
by AnomalousMonk (Archbishop) on Jan 09, 2013 at 13:03 UTC

     .*? can be  .* saving one whole character!

[reply]
[d/l]
[select]

      And s[][] -> s/// for another :) Habits!

      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.
[reply]
[d/l]
[select]

         s/// — A-ha!

[reply]
[d/l]
Re^2: Golf for unique digits
by choroba (Cardinal) on Jan 09, 2013 at 13:36 UTC
    You can drop the final semicolon, too. How comes there are not two of them? :-)
    لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ
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