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.

Input: Consider Input: portland : car. downtown : ?

Output: subway


Input: Consider Input: school : bicycle. spain : ?

Output: airplane


Input: Consider Input: canada : bus. island : ?


Output: boat