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### Re: Re: Re: (Golf) Kaprekar's Process

by MeowChow (Vicar)
 on Jun 17, 2001 at 01:47 UTC ( #89106=note: print w/replies, xml ) Need Help??

in reply to Re: Re: (Golf) Kaprekar's Process

Verrrry cool idea... this can actually come down to 56:
```sub k {
\$_="000"|"@_";/495/?0:1+k(-(\$_=join'',sort/./g)+reverse)
}
The interesting thing about this is that it's not the same as right-formatting the number via sprintf, since the 0 goes to the back, but it doesn't matter because the digits are reordered anyway.
```   MeowChow
s aamecha.s a..a\u\$&owag.print```

Replies are listed 'Best First'.
Re: Re: Re: Re: (Golf) Kaprekar's Process
by Anonymous Monk on Jun 17, 2001 at 02:49 UTC
Yeah, i realized the whole @{[pop]} bit wasn't needed about 20 miles from home, figured someone would've already noticed it by the time i got back.. Here's one more:
```sub k {
\$_=0 x3|"@_";/495/?0:1+k(-(\$_=join'',sort/./g)+reverse)
}
55

--sean
Nice ... It took me a sec to notice it was | and not ||. You can shave off a char by replacing "@_" with pop. I tried to save more, but each time I came up with the same # of chars, just a different way to do it. It almost looks obfuscated now : ), but here's a solution at 54:
```sub k {
\$_=\$-x3|pop;!/495/&&1+k(-(\$_=join\$k,sort/./g)+reverse)
}

Update:Nice catch Sean. I tested it, just not against numbers like 100 233. It looks like the am wins then, unless that can be beaten.

The 15 year old, freshman programmer,
Stephen Rawls

Nope..
by sean (Beadle) on Jun 18, 2001 at 09:01 UTC
Nope, you can't use pop, unless you use it like this: "@{[pop]}" .. The quotes turn it into a string instead of an integer, so the | does a bitstring or instead of a numeric or. If either of the operands are numeric, you'll get the numeric or:
```perl -we 'print "000"|1'
1
that doesn't work for us, we need this:
```perl -we 'print "000"|"1"'
100
--sean

and yeah, i came up with a handful of slightly different attempts that all came in at 55 too.

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