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Given an array of numbers where every number occurs twice except one, how would you find the unique number in O(log n) time?
- Technical PM
- Meta
- Hard
- 15 min
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How to structure your technical PM answer
Stay at product-and-systems altitude: translate user needs into requirements, explain the data flow, and make the important engineering trade-offs visible.
- Clarify users, scale, latency, reliability, privacy, and the critical product journey.
- Separate functional requirements from non-functional requirements and prioritize both.
- Describe the main components and data flow without disappearing into implementation detail.
- Discuss bottlenecks, failure recovery, observability, cost, security, and what changes as usage grows.
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