Design a Parking Lot (OOD)

Problem Design an object-oriented parking lot with multiple levels and several spot types.

Requirements

• Spot types: motorcycle, compact, large.
• Vehicles: motorcycle, car, bus (a bus needs 3 large spots).
• park(vehicle) -> ticket; unpark(ticket) -> fee.
• Pricing by vehicle type and duration.

Areas to design

• The class hierarchy (Vehicle, Spot, Level, ParkingLot, Ticket).
• The spot-finding strategy and vehicle-to-spot fit rules.
• Separation of pricing from allocation, and thread safety for concurrent parks.