The JOI (Japanese Olympiad of Informatics) Open Contest 2014 problems have been added to the DMOJ.

https://dmoj.ca/problems/?search=joi

Many of them use signature grading, unlike most of the DMOJ problemset.

JOI '14 problem 4, Migration, was an output-only task that was judged against other contestant submissions. Since the DMOJ doesn't have the required infrastructure (and it's not worth adding it for one problem), Migration has not been added.