Regex Roulette · #57 · 2026-05-31
Match both singular and plural forms
Difficulty 1/3
How to play
Write a regex that matches all green strings and rejects all red strings. Live feedback shows which strings pass. Shorter patterns score better.
Must match
- cat — not yet evaluated
- cats — not yet evaluated
- dog — not yet evaluated
- dogs — not yet evaluated
Must not match
- catss — not yet evaluated
- dogg — not yet evaluated
- ca — not yet evaluated
- do — not yet evaluated
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Pattern body only — slashes and flags (e.g. /g, /i) aren't part of the input.
0/200 chars
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