Renamed FlightManager to FlightDequeManager.
Moving namespace std to source file of Deque.
Created task debug on Makefile.
Created first version of Hash data structure, using Deque as table.
Created first version of FlightHashManager to center operations on Hash.
Created class Util to handle invalid inputs.
Extracted main logic to a new class called FlightDeque.
Created class FlightHash to manage hash operations.
Changed main to use FlightDeque and FlightHash classes.