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Strings·hard 30 min 120 XP

String Compression

Compress consecutive repeated characters, e.g. 'aaabcc' → 'a3b1c2'. Only compress runs of length 1+.

Examples

  • stringCompress("aaabcc") → "a3b1c2"
  • stringCompress("abc") → "a1b1c1"

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
String Compression · editor

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