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package Calculator;

sub add
{
shift;
my $sum = 0;

	if ( ref ($_[0]) ) {		# assume this HAS to be an ARRAY
		foreach (@{$_[0]}) {
			$sum += $_;
		}
	}
	else {
		foreach (@_) {
			$sum += $_;
		}
	}

	$sum;
}

1;
__END__