Hello, Codeforces!
The China Collegiate Programming Contest (CCPC) is a competitive programming contest series for college students in China, organized by the CCPC Committee, which consists of coaches of the competitive programming teams of Chinese universities. It started in 2015, and this year is the 5th edition of CCPC. There are 4 onsite CCPC contests this year, including three regional contests in Qinhuangdao, Harbin and Xiamen, as well as the CCPC Final in Beijing. Many Chinese universities used CCPC as an opportunity practice before the ICPC regionals.
The 2019 CCPC Harbin Site has recently ended on October 13 in Northeast Forestry University. A total of 273 teams, most of whom were selected from the preliminary online contest, took part in the official onsite contest in Harbin. The problems for this contest were prepared by retired ICPC participants of Zhejiang University, and the head judge was me.
We are glad to invite you to participate in its online mirror: The 2019 China Collegiate Programming Contest Harbin Site in Codeforces::Gym! Please note that the mirror contest will start at Saturday, November 2, 2019, 18:00 (UTC+8). Click on the link to see when it starts in your timezone. We will able to answer your questions during the mirror contest. The ghosts of the onsite participants are available, and you may take advantage of it.
This contest uses ACM-ICPC rules and of course, it is unrated. Team participation is recommended, but it is also possible to participate individually. As usual for Gym contests, you may register for this contest 6 hours before it starts, and you will able to virtually participate and upsolve the problems after it ends.
My thanks go to:
Volunteers and staff from Northeast Forestry University for holding a very success onsite contest.
Problem authors: lsmll, Claris, jiangshibiao, shb123 and reku.
Testers: izban, 300iq, and many members of the competitive programming team of Zhejiang University, some of them are: Todobe, wxx_louisa, zx2017, SoSad, zhangqingqi and lyk248289469.
MikeMirzayanov for the powerful Polygon and Codeforeces system.
The CCPC Committee and the sponsors of the onsite contest.
We kindly ask everyone who has already know the problems not to participate or discuss them before the mirror contest has ended. Hope you enjoy the problems!