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Interview · Technical

Coding interview: problem solving

The candidate explains an approach to four algorithm problems in writing, with optional pseudocode, rather than racing to compile. It suits engineers at any level, because the depth of the follow-ups scales with the answer. Follow-ups push on the edge case that was skipped and on the time and memory cost of the approach.

Suits: Software engineer, Backend engineer, Frontend engineer, Full-stack developer, Graduate software engineer

Questions
4 of 18
Length
35 min
Format
Typed
Levels
All levels
See this interview on a 30-minute call.
AI interviewerScored
Example

  1. Interviewer: Tell me about a time you changed someone's mind at work. How did you go about it?

  2. Candidate: Our team wanted to rebuild the billing page from scratch, and I thought it was the wrong call, so we put together a plan to…

  3. Follow-up

    Interviewer: You said "we". What did you say yourself, and what finally changed their mind?

  4. Scored on

    • Problem understanding20%
    • Approach and correctness35%
    • Edge cases20%
    • Complexity reasoning25%

    Score, reasons and recording. Your team decides.

An example exchange. This interview's own questions open when you use it.

What it listens for, and how much each part counts.

Every answer is scored against this guide, with the reasoning written beside the score. You get the recording or the written answers too, and your team makes the call.

  • Problem understanding20%
    Restates the problem and states assumptions about inputs and limits before solving.
  • Approach and correctness35%
    Reaches a working approach and can explain why it is correct.
  • Edge cases20%
    Names and handles empty, tiny, duplicate and boundary inputs unprompted.
  • Complexity reasoning25%
    States time and memory cost accurately and knows what would improve them.

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    • Data and API design
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    Voice or typed

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