in reply to 1-D Cellular Automata

Sierpinski sieve: 
#!/usr/bin/perl -wl
$_="co";
while (1) { s/..(?=c)/$&^"CO"/eg; s/^/ /; print; }

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Now, why does this work? Because binom(m, n)(mod 2) = n XOR m, so this is just Pascal's triangle (mod 2).

Update: Will work now.

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Re: Re: 1-D Cellular Automata
by RMGir (Prior) on Jun 20, 2002 at 12:36 UTC
    why does this work?

    It doesn't, at least, not with 5.6.1, or 5.005_03.

    Does it need 5.8?

    Edit: As petral points out, the regex will never match. I should have noticed that myself, instead of just trying the code...
    --
    Mike

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      $_="co" will never match /..(?=c)/.

        p
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In Section Cool Uses for Perl