EngMock
AI-assisted coding interview questionHard
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Unique-Letter Word Picker

Fix defects in a small word-game codebase, write an exact search that picks words sharing no letter for the largest total length, then make it fast on large word lists.

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1. Problem Statement

This word-game codebase has failing tests. Read README.md, fix the defects, implement the best-selection search it specifies, then make that search fast enough for the large tests. Use the AI assistant where it helps, and check what it gives you.

2. Live Coding Format

Work in the provided coding workspace while explaining your decisions to the live interviewer. Validation may use inline tests, examples, comments, or a verbal walkthrough.

3. Key Focus Areas

  • 1
    Codebase orientation and debugging
  • 2
    Exact search and tie handling
  • 3
    Verification with your own cases
  • 4
    Performance under a time budget
  • 5
    Reviewing assistant output

4. What Strong Candidates Should Demonstrate

  • Orient in an unfamiliar codebase, trace failing tests to their causes, and fix them without rewriting working code.
  • Implement an exact search with a deterministic tie rule and check it with your own cases.
  • Measure exponential growth and make the search fast without changing its results.
  • Review assistant suggestions against the specification before applying them.

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Practice this problem in the live coding workspace while the interviewer probes your clarification, implementation, trade-offs, and validation.

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Core Concepts

Hidden because they name the technique, which a real interviewer would not tell you.

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DebuggingBacktrackingBitmasksPerformance OptimizationAI Code Review

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