Two analogies that relate places/locations to the associated travel mode is given in the form "A : B. C : ?". "A : B" relates place A to travel mode B. Your task is to replace the question mark (?) with the appropriate travel mode for the given place C, following the "A : B" relation.

Example Input: portland : car. bermuda : ?
Example Output: airplane

Example Input: hospital : ambulance. downtown : ?
Example Output: subway

Example Input: washington : airplane. mall : ?
Example Output:
bus