Tutorial: Design a Parking Lot System

Beginner

+100 XP

Low Level DesignLLDSystem DesignOOPSingletonStrategyFactory

Design a multi-level parking lot system that handles different vehicle types (bikes, cars, trucks), assigns parking spots intelligently, calculates fees, and manages concurrent access from multiple entry/exit gates.

Key requirements:

The system should have a central controller to manage all parking floors and spots
The system should support multiple vehicle types with different sizes, and make it easy to add new vehicle types later
Parking spots should have different sizes and accommodate vehicles of equal or smaller size
The system should support flexible spot selection algorithms (e.g., nearest first, best fit) that can be swapped at runtime
The system should support different fee calculation methods (e.g., flat rate, tiered pricing) that can be swapped at runtime
All entry/exit gates must see the same real-time availability and handle concurrent access safely
The system should issue tickets on entry and calculate fees on exit based on parking duration

🅿️ Interactive Parking Lot

Simulate concurrency & strategy pattern logic

Rate$5.00/hr

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What You'll Build

FR1: Support multiple floors with each floor containing multiple parking spots of different sizes.
FR2: Support three vehicle types with fixed sizes: Bike (SMALL), Car (MEDIUM), and Truck (LARGE).
FR3: Each parking spot has a size (SMALL, MEDIUM, LARGE) and can accommodate vehicles of equal or smaller size.
FR4: On entry, find an available spot using the configured spot selection algorithm, assign to vehicle, generate unique ticket, and return to customer.
FR5: On exit, validate ticket, calculate parking duration and fee using the configured fee calculation method, release spot, and return fee amount.
...and more

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