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Interview practice

Solve complete questions with progressive hints, worked solutions and Python implementations. Each question explains its assumptions and source match. Original interpretations are labelled explicitly.

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Catalogue titles

Public standard problems and original exercises; hidden Trading Interview questions have not been verified.

174 titles have been investigated but remain unresolved. Their missing details are recorded without adding substitute exercises. Every playable question has a guided animated answer; selected questions also have custom diagrams.

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752 matching entries · page 1 of 16

Brain Teasers · Medium

The King's Party

Supported standard problem · Match confidence: high

Company use unverified
About this question’s source match

Title plus Brain Teasers / Out of the Box supports the stated family or explicit original interpretation; each source’s scope is limited below. Public catalogue setup inspected. Timing is stated abstractly as one completed outcome round; no extra rounds are assumed.

There are 1000 labeled wine bottles and exactly one contains a poison detectable by a tester’s death before the party. Any amount is effective; safe wine and mixing do not alter detection. Only one simultaneous test round is possible, and each tester’s result is binary alive/dead. What is the minimum number of testers needed to identify the poisoned bottle, and how are samples assigned?

Assumptions and constraints

  • All measurements, permissions and rules in the statement are exact.
  • No unstated constraints apply.
  • Solve the fixed instance and justify the construction or calculation.

Examples

The scenario stated in the question.
→ 10

Exactly 10 testers suffice, because 512<1000<=1024.

Company evidence · unverified

No company-specific source has been matched to this exercise. Its references support the topic or solution method; they do not establish employer use.

References

Read the supporting material without leaving your question.

Catalogue metadata captured 2026-10-12. Metadata source.