related: #2652 #2653 I found more. https://www.domjudge.org/docs/manual/8.3/problem-format.html https://www.domjudge.org/docs/manual/8.2/index.html The above link wrote: The base of the format is the [ICPC problem package specification](https://icpc.io/problem-package-format/spec/problem_package_format). with a broken link which is fixed on main document. Seems that a patch needs to be applied to older documents.