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my %presence;
my $b = 1;
...
} continue {
    $b *= 2;
}

@list1only = grep { $presence{$_} == 1 } keys %presence;
@list2only = grep { $presence{$_} == 2 } keys %presence;
...
@lists1and2only = grep { $presence{$_} == 1+2 } keys %presence;
@inall = grep { $presence{$_} == 1+2+4 } keys %presence;
# etc