The Listeners
A medium Python mock interview question on DataDriven. Practice with AI-powered feedback, real code execution, and a hire/no-hire decision.
- Domain
- Python
- Difficulty
- medium
- Seniority
- L4
Interview Prompt
Implement an `EventEmitter` with `on(event, listener)` to subscribe, `emit(event, payload)` that returns the payload once per listener currently on that event, and `off(event, listener)` that drops the first matching listener. Then implement `event_broadcaster(op_names, op_args)`, which replays the parallel op sequence against one emitter and collects each result: `None` for the constructor, `on`, and `off`, and the payload list for `emit`.
Summary
Subscribers show up, listen, and sometimes leave.
How This Interview Works
- Read the vague prompt (just like a real interview)
- Ask clarifying questions to the AI interviewer
- Write your python solution with real code execution
- Get instant feedback and a hire/no-hire decision