Code RoomParticle appears in two effects
HardPrep Room Coding #4305

Particle appears in two effects

Vibe & agenticAlgorithms & data structuresSenior–Staff~18 min

An AI agent wrote a pooled-particle system in C#. After heavy use, the same particle visibly appears in two effects at once, and occasionally a 'live' particle vanishes mid-flight. Review the pool's release path and find the reuse bug that double-hands-out an instance.

Implement
run_pool_ops(ops: list[str]) → list[int]
Examples
in[["get","get","release:1","get"]]out[1,2,1]
in[["get","get","release:1","release:1","get","get"]]out[1,2,1,3]
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 18 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.