my @newKeyValuePairs; my %testFields = ('p_customer' => 1, 'p_name' => 1, 'new_users' => 1); while (@keyValuePairs) { my ($key, $value) = (shift @keyValuePairs, shift @keyValuePairs); push (@newKeyValuePairs, $key, $value) unless (exists($testFields{$key})); }