my(%listA) =();
@listA{'one','red','orange','brown','green','blue','scarlett','fourte
+en'} = ();
my(@listB) = ('red','orange','yellow','green','blue','indigo','violet');
foreach my $check (@listB){
   print "$check\n" if(! exists($listA{$check}));
}


__END__
# Output:
yellow
indigo
violet