Hello, Codeforces!
We are happy to invite you to TheForces Round #12 (Double-Forces), which will take place on Apr/28/2023 18:10 (Moscow time)
Editorial is out.
You will have 150 minutes to solve 6 problems.Two of the problems are divided into two subtasks respectively.
We strongly recommend you to read all statements.
All problems were prepared and authored by wuhudsm.
We would like to thank our army of testers: Little_Sheep_Yawn, blxst, O--O, BallBreaker, ExpensiveAC, vikram108, EndlessDreams.
Also we want to thank you for participating in our round.
Note the duration is 2.5h and strongly recommend reading all problems once.
Discord Server (600+ people)
As the setter, I hope you will enjoy the round :)
As a tester give me negative contribution! :)
As a tester give me positive contribution! :)
As a tester, I love testing
What's the approximate difficulty of this round?
Imo it's a DIV2.5 round,suitable for $$$[0,2100]$$$ guys :)
As a tester, hope you'll enjoy! Harder than the former ones i guess lol!
excited
Waiting for an official round sire :)
There is about an hour left before the contest starts and we welcome your registration :)
As a tester, I tested. Hope yall will enjoy the round!
Good problemset (could do only 4 as came 40min later :( )
BTW Any idea about D how to do it?
Editorial
For C2 any hints please
My idea (sum-p1-pn)%(n-1) = 0 we need to find correct pn
This equation is correct. By observing this equation, you know that there may be up to three valid $$$p_ {2n}$$$.