This is an unofficial mirror contest for the China National Olympiad in Informatics, 2020, day 1.

There will be 3 problems to solve in 4 hours, under full feedback (NOI itself is 5 hours, no feedback, aka. spend 2 hours to create your own feedback). This contest is not rated.

However, rpeng is considering running a mirror of the NOI training team system (homeworks, fall tests, winter camp, reports) if there are sufficient interests and performances among CCC-eligible students. That will be determined when we run the NOI`21 mirror in 1~2 weeks (as soon as NAPC is no longer on fire): hopefully this and NOI 19 suffice as practice runs.

For reference, the actual onsite 2020-21 training team (top 50) cutoff was 347/600, and 2019-20 was 372/600.