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Contribute

The archive grows because solvers add to it. Everything submitted is reviewed before it goes live.

Propose a problem

Original, or from a contest not yet archived. Reviewers check for duplicates and assign a provisional rating.

Your best guess. A reviewer sets the published rating, and the archive recalibrates it from how solvers actually do.
Required. A reviewer uses it to check your answer, and if the problem is accepted it becomes the first comment on it, credited to you — so write it for another solver. Nobody sees it until they have solved the problem or given up, so it will not spoil anything.
Optional. Suggestions come from topics already in the archive, but a new name is fine — a reviewer decides.
Preview

This is how a reviewer — and eventually a solver — will see it. Check your LaTeX here before submitting.

Send a note

Something missing, something broken, or a rating that looks wrong. Every note reaches the team.

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