http://www.perlmonks.org?node_id=853502


in reply to Re: The golf course looks great, my swing feels good, I like my chances (Part I)
in thread The golf course looks great, my swing feels good, I like my chances (Part I)

I was relaxing the other day, browsing through some old golfs at shinh's golf site, when I noticed ySas' solution to the "add_some_brainf..._code" game called the getc function. I thought, "that's odd-looking Ruby code with all those $ characters in it", when it dawned on me that it was not Ruby code at all, but Perl! Perl has a getc function? Really? I'm deeply embarrassed to admit, despite having used Perl heavily for 10 years, I did not know that. After picking myself up off the floor, I realised I'd made an appalling oversight in that getc could shorten my previous best Roman Perl solution like so:

$\+=($n="1E@-"%9995)-$\%$n*2while IXCMVLD=~getc;print
53 strokes! What I find interesting here is that while is two strokes longer than for, and getc two strokes longer than <>, yet combining these two longer constructs produces a solution four strokes shorter than:
$\+=($n=IXCMVLD=~$_*"1E@-"%9995)-$\%$n*2for<>=~/./g;print

During the opening months of this competition, Perl led Ruby by 60 strokes to 73. At that stage, I thought it "impossible" for Ruby to ever catch Perl. To my great surprise, I whittled away at my Ruby solution until (to my dismay) it overtook my shortest Perl solution. After more than two years of play, the situation was reversed, with Ruby leading Perl by 53 to 58. Now I was sure that Perl had no chance of ever catching Ruby. As you might expect then, I'm delighted that the shortest known Perl and Ruby solutions are now tied at 53 strokes:

$\+=($n="1E@-"%9995)-$\%$n*2while IXCMVLD=~getc;print n=1;$.+=n/2-n%n=10**(494254%C/9)%4999while C=getc;p$.
And they both use the getc function. :-)

Update: a couple of Ruby equivalents of the Perl solution:

t=0;t+=(n=10**I%9995)-t%n*2while I="IXCMVLD"=~/#{getc.chr}/;p t t=0;t+=(n=10**I%9995)-t%n*2while I="IXCMVLD".index(getc);p t