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Code RoomSingle test case insufficiency
EasyPrep Room Coding #4340

Single test case insufficiency

Vibe & agenticAlgorithms & data structuresEntry–Mid~10 min

An AI assistant wrote you a Python function `days_between(start, end)` that returns the number of days between two date strings like '2026-01-01'. It compiled and returned a number on your first test, '2026-01-01' to '2026-01-10', giving 9. You're ready to call it done. Why is one passing example not enough here, and what specific extra inputs would you run before trusting it?

Implement
days_between(start_date: str, end_date: str) → int
Examples
in["2026-01-01","2026-01-10"]out9
in["2026-03-15","2026-03-15"]out0
What a strong answer looks like

Treat the AI’s output as a draft to verify, not an answer to trust. Name the specific flaw and the input that triggers it, say how you’d catch it (tests, edge cases, reading critically), and how you’d re-prompt or decompose to get it right.

0:00 of about 10 min

Vibe & agentic: describe the solution in plain language (or narrate it) and the coach grades your approach.

Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.