On Sunday, April 26th at 19:00 MSK the 300'th regular Codeforces Round will take place.
I would like to congratulate all Codeforces members and administration on this remarkable milestone. The platform has grown hugely in size and quality since its foundation, has hosted lots of exciting competitions, and has been providing the opportunity to everyone to hone their problem solving and algorithmic mastery. For this we thank the Codeforces platform creator MikeMirzayanov and all the Codeforces crew. Keep up the incredible job, guys!
That being said, I'm excited to announce that the problems on the jubilee three-hundredth Codeforces Round will be set by me, Mikhail Tikhomirov (Endagorion). You may remember the past rounds with my problems: #99, #109, #265, #283, and (in part) #295. I thank the Codeforces problems coordinator Max Akhmedov (Zlobober) for helping me in preparing this round, and Maria Belova Delinur for translating the statements in English. Also, special gratitude to Vladislav Isenbaev (winger), Alex Fetisov (AlexFetisov) and Pavel Kunyavskiy (PavelKunyavskiy) for testing the problemset and help with preparation.
This round will be shared for both divisions and will last two hours and a half (as you can see at the Contests page). The round will feature several ( ≥ 6) problems, varying in difficulty and topics involved. I hope that everyone will find an interesting and satisfying problem just for themselves! The scoring will be announced later.
To add up to the excitement, there are 30 exclusive Codeforces T-shirts to compete for in this round! The top 15 participants will get their T-shirts right away; another 15 will be randomly distributed among those who place in the top 300. Even if you think your chances on being the very best are weak, there are still good odds you will get a treat! =)
That's it. Mark your calendars and come back to compete for the prizes and for the fun!
UPD: there will be 8 problems. The scoring is standard (i.e. not dynamic): 500-1000-1500-1500-2000-2500-3000-3000.
UPD2. In order to choose people getting T-Shirts we will use the following python3.4 code that you can manually run in "custom invocation" tab on Codeforces. It uses an integer as a seed for random generator, this integer should be equal to the last submission number that happened during the contest.
import random seed = int(input()) rnd = random.Random(seed) # all contestants except top-15 contestants = list(range(16, 301)) rnd.shuffle(contestants) tshirts = list(range(1, 16)) + contestants[:15] for x in sorted(tshirts): print(x)
UPD3: Thanks for participating!
The winners are:
The list of places getting the T-shirts are
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 40 46 67 75 80 102 103 144 152 161 169 198 233 243 269. The lucky participants are as follows: bmerry, Egor, Petr, rng_58, scott_wu, Retired_MiFaFaOvO, eatmore, atetubou, qwerty787788, niyaznigmatul, gs12117, W4yneb0t, JoeyWheeler, zxqfl, yeputons, kcm1700 & HYPERHYPERHYPERCUBELOVER (sharing the 40-th place, so both get a T-shirt), piob, Leo_Yu, matrix & Nerevar (sharing the 75-th place), Haghani, ACube, DemiGuo, etal, Emarci15, hlwt, Salvare001, dzy97, FatalEagle, gchebanov & nwi (sharing the 243-rd place), and Solaris (please let me know about any mistakes). Congratulations!
UPD4: At long last, the editorial is up! Enjoy, and sorry for the waiting.