Triangle Golf

A friend of mine recently had an assignment where he had to split up a text file and print it out as a triangle. Of course this was in "c" and so, just because I could I had to see just how simple it would be in perl. The idea is to take a ctriangle.txt file like

a a a a a a a a a
a a a a a a a a a
a a a a a a a a a
a a a a a a a a
[download]

and end up centered over 80 chars

       a
      a a
     a a a
    a a a a
   a a a a a
  a a a a a a
 a a a a a a a
 a a a a a a a
[download]

          The
         same
       principle
      applies to
    any text file,
  basically splitting
 words only on spaces
     or new lines
[download]

My best shot was 132 chars (\n inc). I especially like the new trick I learnt.

/[ 
]+/
[download]

Which matches space/new line combinations.

Well this is the best I could do, after staring at it for half an hour it wasnt getting any shorter.

open F,"ctriangle.txt";sub n{print
" "x(40-$r/2)."$x\n"};for(split/[ 
]+/,join'',<F>){$c=$r,n,$x=''if(
$r=length($x.=" $_"))>$c}n
[download]

- nashdj

Update:
With jeroenes idea, if I undef $/ by assigning it undef from an unused variable (not pretty but we're talking size) its down to 128 chars.

open F,"ctriangle.txt";sub n{print
" "x(40-$r/2)."$x\n"};$/=$w;$_=<F>;
for(split){$c=$r,n,$x=''if(
$r=length($x.=" $_"))>$c}n
[download]

Comment on Triangle Golf Select or Download Code

Replies are listed 'Best First'.
Re: Triangle Golf by jeroenes (Priest) on Apr 24, 2001 at 15:53 UTC
Instead of `split /[ ]+/, join '', <F>` [download] You can also say: `split /\s+/, join '', <F>` or `undef $/; $_=<F>; split` [download] Saves Just Another Character "We are not alone"(FZ)	[reply] [d/l] [select]
Re: Triangle Golf by jmcnamara (Monsignor) on Apr 24, 2001 at 17:14 UTC
This was attempt to see if using `format()` would be shorter. It wasn't. It does use some of Perl's dustier artifacts however: `#!/usr/bin/perl -wall -00n use strict; END{ @_=shift@F; while(@F){ $_=shift @F; $_.=' '.shift@F while(length$_<=length$_[-1]&&@F); push@_,$_ } formline(('@'.('\|'x80)."\n")x@_,@_); print $^A }` [download] Update: Using MeowChow's regex this can be reduced to 89 chars + 6 command line switches. I'm not proud of this: `#!/usr/bin/perl -w -00nal use strict; END{ $_="@F "; @F=1; formline'@'.('\|'x80)."\n",$&and@F=length$&while/.{1,@F}.*? /g; print$^A }` [download] John. --	[reply] [d/l] [select]
Re: Triangle Golf by xtrem (Novice) on Apr 24, 2001 at 19:32 UTC
116 with newlines (by wc) `@ARGV="ctriangle.txt"; sub n{print$"x(40-$r/2)."$x\n"} for(map{split}<>){$c=$r,n,$x=''if($r=length($x.=" $_"))>$c}n` [download]	[reply] [d/l]
Re: Triangle Golf by MeowChow (Vicar) on Apr 24, 2001 at 22:29 UTC
`$c=(@ARGV,$/)='ctriangle.txt';$_=<>.$";y/ / /s;print$"x(40-($c=length$&)/2),"$&\n"while/.{1,$c}.? /g` [download] 102, including the newline ;) update: changed two `' '` to `$"`, saving an additional two characters - liberally aped from jeroenes node :-) update2*: shuffled the $/ assignment into the list assignment, saving another extra char. MeowChow s aamecha.s a..a\u$&owag.print	[reply] [d/l] [select]
Re: Re: Triangle Golf by petral (Curate) on Apr 25, 2001 at 21:15 UTC
Here's some variations on MeowChow's idea above: a perfectly respactable program, about 140 chars (after the #!.../): `#!/usr/local/bin/perl -ln0777 $\ =' '; $c = 0; s/^\s+//; s/\s+/ /gs; while ( s/(.{$c,}?. \|.+$)// ) { print " " x (40 - ($c = 1 + length $1) / 2), $1 }` [download] > triangle.pl a.txt w.txt `a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a The same principle applies to any text file, basically splitting words only on spaces or new lines` [download] a one-liner, 74 chars (+6 extra flag chars): `> perl -ln0777we '$c=0;s/\s+/ /sg;print" "x(40-($c=length$1)/2),$1 whi +le s/(.{$c,}?. \|.+$)//' a.txt w.txt a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a The same principle applies to any text file, basically splitting words only on spaces or new lines` [download] and pretty well golfed, 66 chars (+6 extra flag chars): > perl -ln0777e's/\s+/ /sg;print$"x(40-($c=length$&)/2),$&while s/.{0$ +c,}?. \|.+$//' a.txt w.txt a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a The same principle applies to any text file, basically splitting words only on spaces or new lines > perl -ln0777e's/\s+/ /sg;print$"x(40-($c=length$&)/2),$&while s/.{0$ +c,}?. \|.+$//' w.txt a.txt The same principle applies to any text file, basically splitting words only on spaces or new lines a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a [download] p	[reply] [d/l] [select]
Re: Re: Re: Triangle Golf by MeowChow (Vicar) on Apr 25, 2001 at 22:10 UTC
Very nice paring down, I especially like the conversion from a greedy expression to the minimal one you use, in order to avoid defining $c. Further reduction gives: `perl -ln0e's/\s+/ /g;print$"x(40-($c=length$&)/2),$&while/.{0$c,}? \|.* +/g' ...` [download] 61 chars of code plus 3 modifier chars. MeowChow s aamecha.s a..a\u$&owag.print	[reply] [d/l]
Re: Re: Re: Re: Triangle Golf by petral (Curate) on Apr 26, 2001 at 21:27 UTC
Re: Triangle Golf by japhy (Canon) on Apr 24, 2001 at 19:13 UTC
I offer, at 118 (not counting newlines): `@ARGV='ctriangle.txt';sub n{print " "x(40-$r/2).$x.$\};$/=$w;$_=<>; ($r=length($x.=" $_"))>$=and $==$r,n,$x=''for split;n` [download] `japhy` -- Perl and Regex Hacker	[reply] [d/l]
Re: Re: Triangle Golf by koolade (Pilgrim) on Apr 24, 2001 at 23:04 UTC
The above didn't work for me. $\ is undefined by default so the newline doesn't print and $= is 60 by default so the tests fail. This is the best fix I could come up with, unfortunately with one extra character: `@ARGV='ctriangle.txt';sub n{print " "x(40-$r/2)."$x\n"};$/=$w;$_=<>; ($r=length($x.=" $_"))>$/and $/=$r,n,$x=''for split;n;` [download]	[reply] [d/l]
Re: Re: Re: Triangle Golf by japhy (Canon) on Apr 24, 2001 at 23:05 UTC
I'm sorry. I posted the code without testing it. I had meant `$/` instead of `$\`, but I see that wouldn't have worked. Sorry about that. `japhy` -- Perl and Regex Hacker	[reply]
Re: Triangle Golf by jeroenes (Priest) on Apr 25, 2001 at 02:13 UTC
Works not on words, but 114 char: `@ARGV="ctriangle.txt"; sub n{print$"x(40-$r),@b,$/} @a=map{split}<>;$,=$";while($r++<@a){@b=splice@a,0,$r;n}$r--,n` [download] "We are not alone"(FZ) Update: Most of this is just an adaption of the other code in this nice thread, including the $". I like xterm's idea of map{split}<> very much I must say. But the '$,' was my own creativity....	[reply] [d/l]


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