Background
Today Axon offers a Records Management System (RMS) tailored for police agencies, designed to handle the management of police records. One critical function of this web application is its ability to manage reports created by officers responding to service calls.
These reports describe the officers’ response, including specific references to persons, locations, vehicles, and others—collectively termed as entities. These entities are stored within the RMS to enable reuse and ease of reference in future reports, improving efficiency and consistency in report writing.
User Story
As an officer, I want the ability to subscribe to individual persons, locations, and vehicles, so that I can receive notifications when those entities are referenced in a future report.
这道题围绕警用 RMS 中“实体订阅通知”展开：系统里会把报告中的 Person、Location、Vehicle 等实体沉淀下来，后续新的报告如果再次引用这些实体，需要向已订阅的用户发送通知。解题时通常要把报告解析为实体集合，并维护“实体 -> 订阅者”的映射，以便在新增报告时快速匹配受影响的订阅者并生成通知结果。
