Lld
Low-Level Design
Easy
Dynamic Gym Class Scheduler
Build a backend for a gym class booking application. A GymClass has a fixed capacity and a specific instructor. If a class is full, users join a Waitlist. If a confirmed user cancels, the system must automatically move the first person from the Waitlist to 'Confirmed' status and notify them. The system should prevent overbooking when multiple people try to cancel or join simultaneously.
Key concepts
observer patternconcurrencyfactory pattern
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