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Fundamentals·medium 18 min 75 XP

Leap Year Checker

Return true if a year is a leap year (divisible by 4, but not by 100 unless also by 400).

Examples

  • isLeapYear(2024) → true
  • isLeapYear(1900) → false
  • isLeapYear(2000) → true

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
Leap Year Checker · editor

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