Talked through it step by step and kept pausing to ask if my reasoning tracked.
Start by clarifying requirements and scope, then identify the core domain entities and their relationships. Design the class hierarchy with key methods and attributes, and discuss trade-offs in your design choices. Finally, consider extensibility and edge cases.
Pro tip: Demonstrate awareness of real-world complexities like inventory management, pricing strategies, and concurrency by briefly mentioning them, but don't overcomplicate the core design. Show that you can balance simplicity with extensibility.
Ask questions to understand the scope: Is this for a single store or a chain? What features are needed (inventory, checkout, loyalty programs)? What are the constraints?
List the main objects such as Store, Product, Inventory, Customer, Cart, Order, Payment, and Employee. Define their responsibilities and relationships.
Define classes with attributes and methods. Use inheritance and composition where appropriate, e.g., different payment methods or product categories.
Explain design choices, such as using a singleton for the store or strategy pattern for pricing. Mention trade-offs between flexibility and complexity.
Address how the system can handle new features (e.g., discounts, online orders) and edge cases like out-of-stock items or concurrent updates.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.