Fellow monks,
I had a task to do in Perl yesterday, and it was a simple one.

I had a 25,000-word cracking dictionary file I downloaded, and I wanted to split it up by word length (My motivation is to do with cryptic crosswords).

I just wanted to put all the 10-letter words into a file called 10.words and so on.

So I wrote it the following very dumb way. I knew it was dumb, but I knew it would work. 

while(<>){
chomp($_);
  $len = length($_);
  open(OUTPUT,">>${len}.words");
  print OUTPUT "$_\n";
  close(OUTPUT);
}

[download]

And you've got to admit, it was quick to code.

Then, tortured by how dumb it was, I came back to the problem and figured something else out -- once I'd checked that I could have an array called "@1" and an array called "@2" and so on -- for a while I was convinced that was illegal, though I can't say why.

This is the better way:

while(<>){
  chomp($_);
  $len = length($_);
  if($longest < $len){
    $longest = $len;
  }
  push(@{$len},$_);
}
$"="\n";
for($x=1;$x<=$longest;$x++){
  open(WORDS,">$x.txt") || die "$!";
  print WORDS "@${x}";
  close(WORDS);
}

[download]

Who wants to guess how much smarter the second was than the first?

The first way took 212 seconds (on a computer with a 333MHz chip) and the second took two seconds.

I just thought you might be interested, or have comments.
-- 

($_='jjjuuusssttt annootthhrer
     pppeeerrrlll haaaccckkeer')=~y/a-z//s;print;

[download]

In reply to Extreme Example of TMTOWTDI by Cody Pendant

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