Assuming that each number can only appear once in each list, then the following should work:-

my %counts = ();
foreach my $val (@d1, @d2, @d3) {
    $counts{$val}++;
}
return grep { $counts{$_} == 3 } sort keys %counts;

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In reply to Re: Getting the intersection of n collections. by dtr
in thread Getting the intersection of n collections. by jbrugger

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