in reply to Find duplicate digits

Not very satisfying as a solution, but it works. 

#! perl -slw
use strict;

m[
    (?:^[^0]*0[^0]*0[^0]*$)|
    (?:^[^1]*1[^1]*1[^1]*$)|
    (?:^[^2]*2[^2]*2[^2]*$)|
    (?:^[^3]*3[^3]*3[^3]*$)|
    (?:^[^4]*4[^4]*4[^4]*$)|
    (?:^[^5]*5[^5]*5[^5]*$)|
    (?:^[^6]*6[^6]*6[^6]*$)|
    (?:^[^7]*7[^7]*7[^7]*$)|
    (?:^[^8]*8[^8]*8[^8]*$)|
    (?:^[^9]*9[^9]*9[^9]*$)
]x and print for '0000' .. '9999';

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Update: ... but only for 4 digit numbers. By inverting the logic and only printing numbers that don't contain 3 repeated digits, it should work for numbers of any length. 

#! perl -slw
use strict;

m[
    (?:[^0]*0[^0]*0[^0]*0[^0]*)|
    (?:[^1]*1[^1]*1[^1]*1[^1]*)|
    (?:[^2]*2[^2]*2[^2]*2[^2]*)|
    (?:[^3]*3[^3]*3[^3]*3[^3]*)|
    (?:[^4]*4[^4]*4[^4]*4[^4]*)|
    (?:[^5]*5[^5]*5[^5]*5[^5]*)|
    (?:[^6]*6[^6]*6[^6]*6[^6]*)|
    (?:[^7]*7[^7]*7[^7]*7[^7]*)|
    (?:[^8]*8[^8]*8[^8]*8[^8]*)|
    (?:[^9]*9[^9]*9[^9]*9[^9]*)
]x or m[(?=(\d).*\1)] and print for '000000' .. '999999';

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

Replies are listed 'Best First'.
Re^2: Find duplicate digits
by Anonymous Monk on Feb 15, 2006 at 15:35 UTC
    Thanks, BrowserUk :)

    How do I modify your code to add a new line to each printed number?

[reply]

      If you included -l on your shebang line as I have, it would add the newlines for you, but since many people do not like simple :), you can do this: 

      #! perl -sw
use strict;

m[
    (?:^[^0]*0[^0]*0[^0]*$)|
    (?:^[^1]*1[^1]*1[^1]*$)|
    (?:^[^2]*2[^2]*2[^2]*$)|
    (?:^[^3]*3[^3]*3[^3]*$)|
    (?:^[^4]*4[^4]*4[^4]*$)|
    (?:^[^5]*5[^5]*5[^5]*$)|
    (?:^[^6]*6[^6]*6[^6]*$)|
    (?:^[^7]*7[^7]*7[^7]*$)|
    (?:^[^8]*8[^8]*8[^8]*$)|
    (?:^[^9]*9[^9]*9[^9]*$)
]x and print "$_\n" for '0000' .. '9999';

      [download]
      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]
[d/l]
[select]
Re^2: Find duplicate digits
by Anonymous Monk on Feb 15, 2006 at 15:40 UTC
    Please ignore my earlier post below. I figured that out. Sorry about that...
[reply]

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