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Maybe it's an even dirtier hack, but this one can speed up things a lot.
Your script saves time by skipping chomp. My addition will save time by avoiding a hidden join for each array interpolation. I found this trick when I was benchmarking anagram algorithms.
I used a 116_246 words dictionary, and I got a significative speed improvement, as you can see from the relative times.
$ wc words.english 116246 116246 989075 words.english $ time perl words.english # first hack 1.38 user 0.05 system 0:01.43 elapsed $ time perl words.english # second hack 0.86 user 0.02 system 0:00.88 elapsed
push @{$Word{length$_}},$_ while (<>); # ... print OUT @{$Word{$_}};
$Word{length$_} .= $_ while (<>); # ... print OUT $Word{$_};

BTW: ChOas, congratulations for your sanctification!

There is always room for improvement, though. ...
Combining the first array solution with the other tricks, we have a further 10% improvement.

#!/usr/bin/perl -w use strict; my @words; my $file; $words[length$_] .= $_ while (<>); for (0..$#words) { next unless $words[$_]; $file=$_-1 . ".mine"; open OUT,">$file" or die "Cannot open $file.mine: $!\n"; print OUT $words[$_]; close OUT; };
update (2)
I am afraid that I must have spoiled demerphq's comparison with my previous update. ;)
He very chivalrously included such update and compared the methods shown so far, offering an improvement, that was unfortunately slower than this array + concatenation hack.
Nice Job. Keep up the good work, bro, and many thanks for your analysis.
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In reply to Re: (FASTER) Example of TMTOWTDI by gmax
in thread Extreme Example of TMTOWTDI by Cody Pendant

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