And then thought to use a multi-dimensional hash:

If you have a very large number of lines, using multi-dimensional hashes can consume prodigious amount of memory.

You can achieve the same thing using a single level hash by combining the values into a composite key.

I don't quite follow your criteria for producing your output from the input, but basically rather than the multi-level hash you've shown, do:

my %count;

++$count{ join $;, sort{ $a <=> %b } $F2[1], $F2[2], $F3[2] };

[download]

$; Is a global who values is a control character that won't show up in normal text; and by sorting your values (you may only want to sort two of them rather than all three) you deal with the reversed duplicates problem.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
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In reply to Re: Tallying co-occurence of numbers by BrowserUk
in thread Tallying co-occurence of numbers by K_Edw

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