Codeforces Round #905 (Div. 1, Div. 2, Div. 3)

#	User	Rating
1	tourist	3985
2	jiangly	3814
3	jqdai0815	3682
4	Benq	3529
5	orzdevinwang	3526
6	ksun48	3517
7	Radewoosh	3410
8	hos.lyric	3399
9	ecnerwala	3392
9	Um_nik	3392

#	User	Contrib.
1	cry	169
2	maomao90	162
2	Um_nik	162
4	atcoder_official	161
5	djm03178	158
6	-is-this-fft-	157
7	adamant	155
8	awoo	154
8	Dominater069	154
10	luogu_official	150

Hello, Codeforces!

We are happy to invite you to our experimental round for three divisions, which will take place at Oct/22/2023 14:05 (Moscow time). Please note the non-standard start time for the round. Each division will have 5-7 tasks. The round will be held according to the Codeforces rules and will be rated for all three divisions. A few changes regarding the ratings of participants in this competition:

In Div.3 the rating of participants is less than 1600.
In the Div.2 ranking, participants range from 1600 to 2099.
In Div.1 the rating of participants is no less than 2100.
Please note that after Codeforces Round 904 (Div. 2) the rating will not be recalculated until the end of this competition.

Let us note that two team Olympiads will be held in parallel on this day and the rounds are based on their tasks:

XXI Moscow Team Olympiad, high school students competition based in Moscow that is an elimination contest for All-Russian Team Olympiad.
III Open Team Olympiad UMSh in programming.

We would like to thank everyone who helped me a lot with round preparation.

Coordinators Artyom123 и Vladosiya for excellent coordination and useful advice.
Problem authors 74TrAkToR, Mangooste, TheEvilBird, Tikhon228, teraqqq, valerikk, Dmitry07.
Testers pavlekn, zwezdinv, plagues, SashaT9, Maks_Simenkov, orolik, tmari_sun, OR_LOVe, _why_not_, TimVen74, zarubin, myav, ctraxxd, Gassa, OAleksa, Acanikolic73, AndrewPav, AlphaMale06, NemanjaSo2005, dorijanlendvaj, defnotmee, meOwO, Umi, CIXTEEN, golions, MagentaCobra, FairyWinx, v0s7er, adepteXiao, induk_v_tsiane, Alexdat2000, Be_dos, mr.kolya, kevinxiehk, alexxela12345, talant, daubi for high-quality testing!
MikeMirzayanov for amazing Codeforces and Polygon platforms.

We wish you good luck and high rating!

UPD: One of the problems will be interactive, so please read guide for interactive problems before the contest.

UPD: Score distribution:

Div.3: $$$500-1000-1500-1750-2500-2750-(1750+2000)$$$
Div.2: $$$250-500-1000-(750+1250)-2250-2750$$$
Div.1: $$$(250+500)-750-1000-1250-2000-2750$$$

UPD: Editorial

UPD: We will retest the solutions to the problem div3F and div2C. This may make minor changes, the rating will be recalculated later.

Rev.	By	When	Δ	Comment
en10	RedMachine-74	2023-10-22 17:35:37	79
ru11	RedMachine-74	2023-10-22 17:35:13	87
ru10	RedMachine-74	2023-10-22 17:27:14	131
en9	RedMachine-74	2023-10-22 17:26:20	141
en8	RedMachine-74	2023-10-22 16:15:32	64
ru9	RedMachine-74	2023-10-22 16:13:48	61
en7	Artyom123	2023-10-22 14:52:39	87
ru8	Artyom123	2023-10-22 14:52:06	87
en6	Artyom123	2023-10-22 14:17:29	205
ru7	Artyom123	2023-10-22 14:16:19	205	Мелкая правка: ':Mr.kolya] за качес' -> ':Mr.kolya], [user:kevinxiehk] за качес'
en5	Artyom123	2023-10-22 01:29:47	53	Tiny change: '0$</li>\n<' -> '0$</li>\n<li>Div.1: $(250+500)-750-1000-1250-2000-2750$</li>\n<'
ru6	Artyom123	2023-10-22 01:29:29	53	Мелкая правка: '0$</li>\n<' -> '0$</li>\n<li>Div.1: $(250+500)-750-1000-1250-2000-2750$</li>\n<'
en4	RedMachine-74	2023-10-21 19:59:46	193
ru5	RedMachine-74	2023-10-21 19:59:13	186
en3	Artyom123	2023-10-21 14:15:13	162
ru4	Artyom123	2023-10-21 14:14:08	176
en2	Artyom123	2023-10-21 14:02:37	28	Tiny change: '023-10-19]' -> '023-10-19], [user:Dmitry07,2023-10-19]'
ru3	Artyom123	2023-10-21 14:00:59	28	Мелкая правка: '023-10-19]' -> '023-10-19], [user:Dmitry07,2023-10-19]'
en1	RedMachine-74	2023-10-20 20:02:15	2607	Initial revision for English translation
ru2	RedMachine-74	2023-10-20 19:51:15	405	Мелкая правка: 'ов меньше 1600. </li>\n<' -> 'ов меньше $1600$. </li>\n<' (опубликовано)
ru1	RedMachine-74	2023-10-20 19:42:37	2196	Первая редакция (сохранено в черновиках)

History