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Hi all.
I've got the following question:
I've got n arrays, that all contain data.
I want to return a new array, containing only the data, that exist in all n arrays mentioned above.
(i hope i'm clear in what i want)
Right now, my following solution works, but i wonder if there is a more clever and fast way to do this:
# If my datasets contain # @1 = 1,2,3,4,5 # @2 = 2,3,6,7,8,8,8,9,10 # @3 = 5,6,2,3 # # the result should be: 2,3 # my %intersection; my @result; foreach my $dataArray(@AllArraysIHave) { my %lookuptable; foreach(@{$dataArray}) { if (!$lookuptable{$_}) { $lookuptable{$_} = 1; $intersection{$_}++; } } } my $amnt = scalar(@AllArraysIHave); foreach my $key (keys %intersection) { if ($intersection{$key} == $amnt) { push @result, $key; } } return \@result;
*update*
Thanks for all the fast replies
lima1, indeed, it has to work for duplicate items as well. (changed the example a little.)

"We all agree on the necessity of compromise. We just can't agree on when it's necessary to compromise." - Larry Wall.

In reply to Getting the intersection of n collections. by jbrugger

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