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1. Problem Statement
Design a car rental system: customers get a quote and reserve a vehicle category for a date range, pick up an assigned vehicle, and return it with an inspection that may add charges for mileage, fuel, or lateness. No vehicle can be double-booked for overlapping periods. Start by clarifying scope and the core objects.
2. Live Coding Format
Work in the provided coding workspace while explaining your decisions to the live interviewer. Validation may use inline tests, examples, comments, or a verbal walkthrough.
3. Key Focus Areas
- 1VehicleCategory/Vehicle and per-category availability
- 2Half-open DateRange and no-overlap invariant
- 3RateStrategy and quote snapshot
- 4Vehicle assignment at pickup and return inspection charges
4. What Strong Candidates Should Demonstrate
- Model vehicle categories vs. vehicles and category reservation vs. vehicle assignment.
- Design a half-open rental DateRange and prevent overlapping rentals of a vehicle.
- Price rentals behind a replaceable rate strategy and snapshot the quote.
- Validate return readings (odometer/fuel) and compute extra charges in cents.
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Practice this problem in the live coding workspace while the interviewer probes your clarification, implementation, trade-offs, and validation.
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Object-Oriented DesignDomain ModelingValue ObjectsStrategy Pattern
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