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Practice · no official grade

Code arena

Twelve exercises on agents, APIs, retrieval and operating systems. The code runs only in your browser, in JavaScript, with no server and no key.

A short intro: operating systems, files and APIs

Classify an API response

Easy

API · Intro

A server returns a numeric status code. Return "ok" for 2xx, "denied" for 401 or 403, "missing" for 404, "server" for 5xx, and "other" for everything else.

Examples

  • solve(200) → "ok"
  • solve(404) → "missing"
  • solve(302) → "other"

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