Perl Golf idea

sweepy838 has asked for the wisdom of the Perl Monks concerning the following question:

Replies are listed 'Best First'.
Re: Perl Golf idea by davido (Cardinal) on Apr 27, 2012 at 21:46 UTC
Why don't you go ahead and post a Perl version of your own here, just for a bit of fun. The worst you could do is just transcribe the C version over to a Perl equivalent, and then you'd be showing us a target to try to best. Dave	[reply]
Re^2: Perl Golf idea by sweepy838 (Acolyte) on Apr 27, 2012 at 22:00 UTC
haha yes the WORST i could do is convert it to perl! im ashamed of posting it yet.. im trying to make it better. but here is the c version: string myword; string wlist = "dict.txt";string line; int strLen = myword.length( +);int c = 0; ifstream cfile(wlist); if (cfile.is_open()) { while (cfile.good()) { getline (cfile,line); if (strLen == line.length()) { bool match[strLen];string used[strLen];int matchcount = + 0; for (int i = 0; i < strLen; i++) { string ch = myword.substr(i, 1); for (int y = 0; y < strLen; ++y) { string kh = line.substr(y, 1); if (ch == kh) { if (used[y] == ch) match[matchcount] = 0; else { used[y] = ch; match[matchcount] = 1; matchcount++; break; } } } } c = 0; for (int t = 0; t < strLen; t++){if (match[t] == true) + ++c; } if (c == strLen) { return line; } delete [] match; } } cfile.close(); } [download] I have a feeling that people think i'm getting them to do my "homework" ? seriously?	[reply] [d/l]
Re^3: Perl Golf idea by GrandFather (Saint) on Apr 27, 2012 at 23:38 UTC
Rewritten in Cerl (C++ transliterated into something that a Perl interpreter in a good mood may care to execute): my $myword; my $wlist = "dict.txt"; my $strLen = length $myword; open my $cfile, '<', $wlist or die "Can't open $wlist: $!\n"; while (defined (my $line = <$cfile>)) { next if $strLen != length $line; my @match; my @used; my $matchcount = 0; for (my $i = 0; $i < $strLen; $i++) { my $ch = substr $myword, $i, 1; for (my $y = 0; $y < $strLen; ++$y) { next if $ch ne substr $line, $y, 1; if ($used[$y] eq $ch) { $match[$matchcount] = 0; } else { $used[$y] = $ch; $match[$matchcount] = 1; $matchcount++; last; } } } my $c = 0; for (my $t = 0; $t < $strLen; $t++) { ++$c if ($match[$t]); } return $line if ($c == $strLen); } close $cfile; [download] This is of course completely untested and not what I would consider to be Perlish, although it is strict compliant. Note that the minor structure changes I made could actually be pushed back to the original C++ code to clean up that code somewhat. True laziness is hard work	[reply] [d/l]
Re: Perl Golf idea by thundergnat (Deacon) on Apr 30, 2012 at 20:01 UTC
Here's a kind of half-assed one. Feed it the path to the dictionary file and a word and it will return all the matches. I.E. `perl -e"sub w{join'',sort@_[0]=~/./g};$w=w pop;($w eq w$_)&&print for<>" ./dict.txt acert` returns: caret cater crate react trace (with the dict.txt file I had. YMMV).	[reply] [d/l]
Re^2: Perl Golf idea by tobyink (Canon) on Apr 30, 2012 at 22:51 UTC
Nice. I've managed to knock off twelve characters though... `@_[0]` can be replaced with `pop`. This needs whitespace before it, but it's still shorter. Savings: 1 character. `eq` can be replaced by the smart match operator, allowing the whitespace around it to be dropped. Savings: 2 characters. Semicolon after sub definition not needed. Savings: 1 character. Now we've got: `perl -E'sub w{join"",sort pop=~/./g}$w=w pop;($w~~w$_)&&print for<>' . +/dict.txt acert` [download] But, hell, we can go shorter. Let's switch from the `join"",...` construct with the babycart operator inside an interpolated string... `"@{[...]}"`. Can't remember why I did this - doesn't actually reduce the size of the code, but I think it was necessary for some of the later stuff. `perl -E'sub w{"@{[sort pop=~/./g]}"}$w=w pop;($w~~w$_)&&print for<>' . +/dict.txt acert` [download] Next, we stop passing a parameter to the `w` function, and use `$_` instead. This means that we can take advantage of the fact that regular expressions get applied to $_ by default, giving us massive savings inside the function. Outside the function it's a mixed blessing. We need to assign that `pop` to `$_` giving us a whole new statement. But we don't need to pass anything to `w` on either of its invocations, and we can drop the parentheses around the smart match comparison. `perl -E'sub w{"@{[sort/./g]}"}$_=pop;$w=w;$w~~w&&print for<>' ./dict.t +xt acert` [download] Those two assignments in the middle started to grind my gears. I figured there must be a way to ditch the semicolon between them... and there is! The `w` function no longer cares about what parameters it's passed. `perl -E'sub w{"@{[sort/./g]}"}$w=w$_=pop;$w~~w&&print for<>' ./dict.tx +t acert` [download] I could go two characters shorter, but only swapping from `print` to `say` which adds unsightly blank lines to the output. UPDATE: five characters more. Smart match can deal with arrayrefs! `perl -E'sub w{[sort/./g]}$w=w$_=pop;$w~~w&&print for<>' ./dict.txt ace +rt` [download] `perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'`	[reply] [d/l] [select]
Re^3: Perl Golf idea by JavaFan (Canon) on May 01, 2012 at 14:57 UTC
One character less: `perl -nlE'sub w{[sort/./g]}INIT{$w=w$_=pop}$w~~w&&say' ./dict.txt acer +t` [download] And if you don't mind the (second) argument getting printed, another 3 chars less: `perl -nlE'sub w{[sort/./g]}$w\|\|=w$_=pop;$w~~w&&say' ./dict.txt acert` [download]	[reply] [d/l] [select]
Re^4: Perl Golf idea by brx (Pilgrim) on May 01, 2012 at 20:58 UTC
Re^5: Perl Golf idea by thundergnat (Deacon) on May 02, 2012 at 17:08 UTC
Re^3: Perl Golf idea by thundergnat (Deacon) on May 01, 2012 at 14:09 UTC
Umm. Wow. I knew there was room for ~~improvement~~ reduction but... tobyink++	[reply]
Re: Perl Golf idea by brx (Pilgrim) on May 02, 2012 at 13:41 UTC
Here is a summary of replies to this little informal golf contest. I hope there will be more replies. thundergnat `perl -e'sub w{join"",sort@_[0]=~/./g};$w=w pop;($w eq w$_)&&print for<>' ./dict.txt acert` tobyink `perl -E'sub w{[sort/./g]}$w=w$_=pop;$w~~w&&print for<>' ./dict.txt acert` JavaFan `perl -nlE'sub w{[sort/./g]}INIT{$w=w$_=pop}$w~~w&&say' ./dict.txt acert` brx `perl -E'@a=sort pop=~/./g;print grep@a~~[sort//g],<>' ./dict.txt acert` JavaFan, with the second argument getting printed (a dummy line must be added at the begining of dict.txt) `perl -nlE'sub w{[sort/./g]}$w\|\|=w$_=pop;$w~~w&&say' ./dict.txt acert` brx, with an extra newline after last line printed `perl -E'@a=sort pop=~/./g;say grep@a~~[sort//g],<>' ./dict.txt acert` Update: thundergnat `perl -nlE'($w//=[sort pop=~/./g])~~[sort//g]&&say' ./dict.txt acert`	[reply] [d/l] [select]


go ahead... be a heretic
	PerlMonks