Hi, Codeforces!

We are glad to invite you to take part in Codeforces Round #569 (Div. 1) and Codeforces Round #569 (Div. 2), which will be held on Friday, June 21, 2019 at 19:35. The round will be rated for all participants from both divisions.

Problems for the round have been proposed by Ivan ScreaMood Fedorov, Kyrill Choopa_choops Bessonov, Mukhammadjon Mr.Hakimov Hakimov, Fedor osaaateiasavtnl. Ushakov and me, Dmitry DmitryGrigorev Grigoryev.

The round have been prepared by us, Dmitry DmitryGrigorev Grigoryev, Fedor osaaateiasavtnl. Ushakov, Dmitry TheWayISteppedOutTheCar Piskalov and Mukhammadjon Mr.Hakimov Hakimov.

We'd like to give thanks to Ildar 300iq Gainullin for excellent coordination of the round, to Sooke Sooke Gnar, Xiuhan sunset Wang, Ziqian TLE Zhong, Junzhao FizzyDavid Yang, Jiaxuan samjia2000 Gao for testing and to Mike MikeMirzayanov Mirzayanov as well for his unbelievable Codeforces and Polygon platforms!

Participants in each division will be offered 5 problems and 2 hours to solve them. During the round you will be helping for pupils of one usual Moscow school. Score distribution will be announced, traditionally, closer to the start of the contest

Good luck!

Hello, Codeforces!

We are glad to invite you to take part in Codeforces Round #568 (Div. 2), which will be held on Jun/19/2019 17:45 (Moscow time). The round will consist of 7 problems (possibly, plus subproblems). It will be rated for Div. 2 participants.

We, geranazavr555 and cannor147, are students of ITMO University. And we have recently joined the developers team of Codeforces and Polygon. We have prepared this round for more careful acquaintance with the system. We hope that you will enjoy the competition.

Initially, we had prepared the round for Div. 3, but after testing, it became clear that this round is harder than usual such rounds. MikeMirzayanov suggested to make this to be rated for the second division.

Many thanks to MikeMirzayanov for the tremendous work on the creation and development of Codeforces and Polygon and coordinating our work. Also, special thanks to Vshining, PikMike, ZeroAmbition, Vovuh, Lewin, Dave11ar, T-D-K and Azat_Yusupov for testing the round.

Good luck!

UPD1:

The scoring distribution will be: 500 — 1000 — (1000 + 750) — 2000 — 2250 — 2750 — (2750 + 750). The round will last 2 hours and 15 minutes.

UPD2:

Congratulations to the winners:

1. 2om_neek

2. m1sch3f

3. AreEduRoundsEducational

4. ashutosh450

5. LOVE_BELUGAS

UPD3:

Editorials are available here.

Hi!

Tomorrow will take place All-Russian olympiad for students of 5-8 grades, in the name of Keldysh. Good luck to all the participants! Olympiad is conducted under the guidance of the Moscow Olympiad Scientific Committee, in particular GlebsHP, ch_egor, Endagorion, gritukan, Zlobober, _meshanya_, _kun_ and, of course, Helen Andreeva.

We are happy to announce the codeforces round based on the problems of this olympiad! It will be a Div. 2 round, which will take place at Jun/16/2019 12:35 (Moscow time). You might have already participated in rounds based on the school olympiads, prepared by Moscow Olympiad Scientific Committee (rounds 327, 342, 345, 376, 401, 433, 441, 466, 469, 507, 516, 541, 545)

The problems of this olympiad were prepared by voidmax, alexey_kuldoshin, ch_egor, Nebuchadnezzar, achulkov2, manoprenko, V--gLaSsH0ldEr593--V, Endagorion.

Thanks KAN for his help in organizing the Codeforces version of this contest and MikeMirzayanov for the Codeforces and Polygon.

Also I would like to thank the Tinkoff company and personally Tatyana Kolinkova for organizing the onsite competition.

Good luck!

Scoring: 500-1000-1500-1750-(2000+750)

upd. Congratulations to winners!

Div. 2:

1. thecodinglizard
2. baIuteshih
3. Cong1500DanPaiXia0
4. Cottonyeti
5. HatsuneMikuo

unofficial Div. 1:

1. Radewoosh
2. isaf27
3. chemthan
4. uwi
5. kmjp

The editorial will be published soon.

upd. the editorial was published.

We glad to announce the first ICPC Alumni event happening in Russia!

ICPC Foundation is currently working on building the ICPC Alumni association across the globe and we're happy to announce our big reunion event to be held at a very special location — ITMO University, St.Petersburg, Russia.

We will be extremely honored to welcome you and your colleagues/classmates on this special day. In addition to this being a fun reunion for local ICPC participants, we will be recognizing the accomplishments of various ICPC volunteers who make the show happen each year!

ICPC Alumni Reunion Dinner will be held on Saturday, July 6th, 2019 at ITMO University (St.Petersburg, Russia) on Birzhevaya line 14-16. There will be a reception that begins at 5pm, with dinner to follow at 6pm. And those who want — may join us for a boat trip following the dinner.

Please be sure to RSVP via this form to secure your place before June 23, 2019:

Register

ICPC Executive Director Bill Poucher will be in attendance, and various other judges, staff, and coaches. We would be honored if you can make it as well, and partake in the festivities.

We are unfortunately unable to welcome all outside guests but have done our best to invite as many ICPC alumni as possible from Russia and Europe. Please feel free to forward this invitation to any other finalists/regional participants that you know to be in the area. You can also send their contact information to manager@icpc.global so that we can add them to the invitation list if you'd prefer.

If you have any photos of your time as an ICPC contestant, coach or volunteer that you would like to be shown at the event added to the ICPC History Archives and/or shared over ICPCNews, please share it with us!

We’re looking forward to enjoying a fun reunion and celebration of all things ICPC!

안녕하세요, 코드포스! (Hello, Codeforces!)

I'm super happy to introduce you to Codeforces Round #566 (Div. 2), which will take place on Jun/11/2019 16:05 (Moscow time).

The round will be rated for all Division 2 participants, yet any Division 1 participants are welcome to join us out of competition.

You will be given 6 problems and 2 hours to solve them. Score distribution will be announced later.

The listed handles below are contributors. Thank you for all who listed!

• Problem idea: McDic (ABDEF), arsijo (C)
• Problem preparation: McDic
• Coordinator: arsijo
• Testers: Lawali , final_child , Dr_Park , pllk , Aleks5d , antoshkin
• Father of Codeforces and Polygon: MikeMirzayanov

This is my first Codeforces contest ever. I hope everyone who will join this contest enjoy. Thank you!

WINNERS:

1. Castor
2. thecodinglizard
3. puyu_liao
4. UoA_Kanade
5. It5t
6. LucaSeri
7. orz_liuwei
8. emengdeath
9. ashutosh450
10. hyfzbtrs

UPDATES:

1. Let me spread the meme from McDic Minecraft Telegram group — Ggungah.
2. Score distribution is 500-750-1250-2000-2250-2750.
3. Editorial is available.
4. Congratulations for the winners!
5. I am sorry for weak systests for B and F. Sorry again.

<almost-copy-pasted-part>

Hello! Codeforces Round #565 (Div. 3) will start at Jun/09/2019 17:35 (Moscow time). You will be offered 6 or 7 problems (or 8) with expected difficulties to compose an interesting competition for participants with ratings up to 1600. Probably, participants from the first division will not be at all interested by this problems. And for 1600-1899 the problems will be too easy. However, all of you who wish to take part and have rating 1600 or higher, can register for the round unofficially.

The round will be hosted by rules of educational rounds (extended ACM-ICPC). Thus, during the round, solutions will be judged on preliminary tests, and after the round it will be a 12-hour phase of open hacks. I tried to make strong tests — just like you will be upset if many solutions fail after the contest is over.

You will be given 6 or 7 (or 8) problems and 2 hours to solve them.

Note that the penalty for the wrong submission in this round (and the following Div. 3 rounds) is 10 minutes.

Remember that only the trusted participants of the third division will be included in the official standings table. As it is written by link, this is a compulsory measure for combating unsporting behavior. To qualify as a trusted participants of the third division, you must:

• take part in at least two rated rounds (and solve at least one problem in each of them),
• do not have a point of 1900 or higher in the rating.

Regardless of whether you are a trusted participant of the third division or not, if your rating is less than 1600, then the round will be rated for you.

Thanks to MikeMirzayanov for the platform, help with ideas for problems and for coordination of my work. Thanks to my good friends Mikhail PikMike Piklyaev, Maksim Ne0n25 Mescheryakov and Ivan BledDest Androsov for help in round preparation and testing the round.

Good luck!

I also would like to say that participants who will submit wrong solutions on purpose and hack them afterwards (example) will not be shown in the hacking leaders table.

</almost-copy-pasted-part>

UPD1: Big thanks to Um_nik, Rudy358, nigus, opukittpceno_hhr and Temotoloraia for testing the round! And also big thanks to my dear friends Ivan BledDest Androsov, Roman Roms Glazov and Mikhail PikMike Piklyaev for help with round preparation!

UPD2: Editorial is published!

UPD3:

Congratulations to the winners:

Congratulations to the best hackers:

And finally people who were the first to solve each problem:

Hi!

We are glad to invite you to take part in Codeforces Round #564 (Div. 1) and Codeforces Round #564 (Div. 2), they will be held on Jun/07/2019 15:05 (Moscow time). The round will be rated for both divisions.

Participants in each division will be offered 6 problems and 2 hours to solve them, including 4 shared problems for both divisions, and one of them has two versions with the only difference in constraints.

The problems were written and prepared by me, Sooke, QAQAutoMaton, ODT, ccz181078, rushcheyo and PinkRabbit.

Great thanks to 300iq for coordinating and testing the round, we enjoyed the experience of preparing a round with him.

Thanks to Um_nik, KAN, isaf27, xht37, ButterflyDew and DKACVenus for testing the round, too.

Of course, thanks to MikeMirzayanov for amazing systems Codeforces and Polygon!

Last but not least, thanks to everyone who participates in this round, for making our efforts meaningful.

Both English and Chinese editorials will be available after the contest.

UPD 1: The scoring distribution will be:

• Div.2: 500 — 1000 — 1500 — 1750 — (1250 + 1250) — 2750

• Div.1: 500 — 750 — (750 + 750) — 1750 — 2500 — 2750

UPD 2: Congratulations to the winners!

Div.1:

1. CauchySheep

2. maroonrk

3. WA_TLE

4. zeronumber

5. nhho

Div.2:

1. foreverlasting

2. wifiiiiii

3. liuxiao

4. Joysh

5. YenSean

UPD 3:

The English Editorial and the Chinese Editorial are published.

This season is promised to be exciting! It's high time to start preparing for the ICPC World Finals 2020 in Moscow. Follow our website to check the registration updates.

We are opening registration for the Discover Grodno programming workshop to prepare for the ICPC season. From 7 to 14 of July we invite students of B and C divisions to Belarus! The camp will be held at the Yanka Kupala State University of Grodno. Apply now to get the lowest price and request the payment bill if your university or sponsor would like to pay for you.

As you remember July 6 — 13 we will meet in the beautiful city of Vladivostok at the Discover Vladivostok Workshop. Registration is open for A, B, and C divisions! Students will study on the Far Eastern Federal University campus. Apply now and request the payment bill asap to get the lowest price and other bonuses.

What else is coming up?

• September, 7-14: Baikal, Russia (Div. C, D)
• September, 21-28: Singapore (Div. А, В/С)
• October, 5-13: Riga, Latvia: (Div. А, В/С)
• November, 5-14: Moscow International Workshops ICPC (Div. A, B)
• April: Moscow Pre-finals Workshop ICPC (Div. A, B)

Looking forward to see you soon!