Sum of Their Parts
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
You're collapsing a raw event stream into one record per user, where each event carries a `user_id`, an `event_type`, and an `amount`. For each user, total their amounts within each `event_type` so every distinct type they triggered becomes one key on that user's record.
Summary
A stream of raw actions, folded into one portrait per person.
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