Anagram finder

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

I'm trying to write an anagram finder that searches through /usr/dict/words. I know there were some other posts on this, but I tried to write my own. Basically, I wanted it to do this:

% anagram_finder.pl elloh
hello
%
[download]

I have some code that does it using a for loop, but I wanted to get it to work using "grep". I thought it would be cleaner and nicer. This doesn't work, though I have been trying very hard to find my mistake but I have been unlucky so far:

open DICT, "</usr/dict/words" or die "no more words: $!";
$a = join "", sort split "", lc shift;
print join "\n", grep {$a eq join "", sort split "", lc} <DICT>;
[download]

Any help would be greatly appreciated.

Paul Chou

Comment on Anagram finder Select or Download Code

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Re: Anagram finder by jeroenes (Priest) on Apr 24, 2001 at 09:43 UTC
You're bitten by newlines. `print join "\n", grep {chomp; $a eq join "", sort split "", lc} <DICT> +;` [download] Jeroen "We are not alone"(FZ) And yes, I tested it. Is not bothered by the sub-grief, apparently	[reply] [d/l]
Re: Re: Anagram finder by pchou (Novice) on Apr 24, 2001 at 22:12 UTC
Thank you all very much. I'm still pretty new to perl, and I guess I got confused with "chop" and "chomp" which giving me problems (and why I didn't include it). Paul	[reply]
Re (tilly) 1: Anagram finder by tilly (Archbishop) on Apr 24, 2001 at 09:40 UTC
The automagic "is or isn't there a sub there?" is giving you grief. It is trying to treat split as the sort sub, and not as part of how you get a list into the sort. UPDATE jeroenes is correct. I should have tested before tossing that out. I guess it is better about finding keywords. But try putting a subroutine that you have created there and it will be cheerfully abused: `sub my_split { split "", shift; } print join "", sort my_split("qwerty");` [download]	[reply] [d/l]
Re: Anagram finder by frankus (Priest) on Apr 24, 2001 at 19:15 UTC
You could try for more lines and less memory strain: `open DICT, "</usr/dict/words" or die "no more words: $!"; $a = join "", sort split "", lc shift; for(<DICT>){ $b = lc($_); chomp($b); $b = join("",sort(split //,$b)); if($a eq $b){print} }` [download] Hint: Take a look at Mastering Perl Algorithms. This way, the contents of dictionary aren't loaded into an array, advisable if you're playing on anything smaller than an Enterprise Server. I like the concise style of code though ;0). -- Brother Frankus.	[reply] [d/l]