Rules

Scoring

Fewer products rank first. Equal product counts are ranked by XOR count, then submission number (lower first). The verifier computes every score. The file format and the exact scoring rule are on the Overview tab.

What is public

Scores, ranks and the number of entries are public.
Each participant chooses whether a submission is public. For a public submission anyone can see the verifier report and the attached code, and download the file once it is accepted. For a private one, only its score and rank are public. New accounts start with private submissions; the default can be changed on the account page.
A public submission's page, including the verifier report, can be opened by anyone, for example from the leaderboard.

Limits

Each participant may submit 30 files per problem per UTC day. At most 10 submissions may be queued or running at once across all problems, and each file must be no larger than 20 MiB. Errors and rejected files count toward the daily number. An attached code file or notebook may be up to 5 MiB.

Corrections

Records that depend on a verifier bug are removed once the bug is confirmed.

Access

Browsing is public. To submit, register with an email address and confirm it. Then upload files on a problem's Submit page, or create an API token on your account page.