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;

[download]
*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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