You are implementing a simplified bus boarding simulator. Model: - `Person` has at least: - `id` (string/int) - `priority` (boolean): if true, they should board before non-priority riders. - `wheelchair` (optional): if present, the person uses a wheelchair. - `capacityCost` (int): how many capacity units they consume when boarding (defaults to 1 for a normal rider; wheelchair riders may have different costs). - `Bus` has: - `totalCapacity` (int) - `maxWheelchairs = 2` Task A — Priority boarding: - Given a waiting line of people (in arrival order) and a bus with remaining capacity, board as many people as possible. - Priority riders should be boarded before non-priority riders. - Preserve relative order within the priority group and within the non-priority group (stable ordering). - Return (1) the list of boarded riders in the order they boarded and (2) the remaining waiting line. Task B — Explain tradeoffs: - Explain why you implemented it that way. - Provide at least one alternative approach and compare time/space complexity and maintainability. - Mention what you would change for “real production” (e.g., extensibility, fairness/starvation, configurability). Task C — Unit tests: - Write unit tests for Task A (and for Task D below if time). Specify key edge cases. Task D — Add wheelchair constraints: - Extend boarding logic with these rules: - A bus can carry at most 2 wheelchair riders. - Each wheelchair rider consumes `capacityCost` units (not necessarily 1). - Non-wheelchair riders consume 1 unit. - Continue to respect priority boarding and stable ordering within groups. You may define your own function signatures (e.g., `board(bus, waitingQueue)`).