The Ones That Come Back
A easy Python mock interview question on DataDriven. Practice with AI-powered feedback, real code execution, and a hire/no-hire decision.
- Domain
- Python
- Difficulty
- easy
- Seniority
- L3
Interview Prompt
A data-quality check on an event export turned up a column of integer `ids` that should be unique but isn't. Return the id values that appear more than once, from smallest to largest.
Summary
In a column that promised uniqueness, some values kept their seat. Name them.
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