The Sum of Its 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
- mid
Interview Prompt
A 3D modeling tool stores each design as an assembly tree: every component carries a `name`, a `quantity` (how many of it appear inside its parent, defaulting to 1 when absent), and a `children` list of sub-components nested arbitrarily deep. Roll the tree up into the total count of each leaf part (a component with no children, including one whose `children` list is empty), where a part's count is the product of the quantities along the path from the root down to it, added up across every place that part appears.
Summary
Every assembly hides smaller ones. Count what it really takes to build.
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