← Practice
Algorithms·medium 18 min 75 XP

Prime Checker

Return true if a number is prime.

Examples

  • isPrime(7) → true
  • isPrime(8) → false

Constraints

  • Keep the required function name so the tests can find it
  • Return a value instead of only logging it
  • Do not mutate inputs unless the challenge asks you to
Prime Checker · editor

Code runs in an isolated Web Worker with a 3-second timeout — no DOM access, and it can never hang the page.