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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

Programming · Medium

Longest Run of Distinct Characters

Supported standard problem · Match confidence: high

Company use unverified
About this question’s source match

The title and Programming / String Manipulation classification fit the linked public problem. This entry uses an independently worded practice statement and original implementation. The public title and category identify a standard problem family; the private Trading Interview statement has not been inspected.

Implement solve(s) returning the length of its longest contiguous substring with no repeated character. Distinguish characters exactly, including spaces and case.

Assumptions and constraints

  • Characters are Python Unicode code points, not grapheme clusters.
  • 0 <= len(s) <= 1000000

Examples

s="abbae"
→ 3

bae has three different characters.

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.