By tourist, 5 weeks ago, translation, In English

Hello everyone!

We, the RGBTeam (qwerty787788, Romka and tourist), are huge fans of heuristic programming competitions and are quite saddened by the fact that they are becoming less and less frequent each year. One day, we decided to organize our own competition :) Despite the fact that such ideas often remain just ideas, this time we have a serious mindset, and now we want to invite you all to participate in the first — and hopefully not last — Code Weekend #1!

The competition will be held in a format quite similar to ICFPC/Google Hashcode — there will be one problem and several dozen tests for it. You will need to submit just an output according to the rules of the problem for each test, which can be obtained using any algorithms, written in any language, and running for any duration of time. Midway through the competition, the problem statement will be expanded, and new tests will be added.

The competition starts on June 7th at 21:00 UTC and will last 48 hours. A day after it begins, on June 8th at 21:00 UTC, a second, expanded version of the problem along with a set of tests for it will be released. The competition ends another day after the release of the second version, on June 9th at 21:00 UTC.

The expanded version of the problem will be a superset of the basic version. For instance, if the problem is "given a chess position, find the best move," the basic version may only include pawns, bishops, and knights, while the expanded version will use rooks and queens.

The competition is team-based, and there is no limit on team size, but we've tried to balance the problem in a way that larger teams don't have a significant advantage over smaller ones. Therefore, the recommended team size is 1-4 people.

Unlike ICFPC, the focus of the competition will be on heuristic algorithms rather than functional programming (although in recent years ICFPC hasn't been focused on FP either).

Attention! The contest will be held on the website, you need to register there (once per team). All the announcements during the competition will be in the Discord chat, so join it via the link Be sure to invite your friends, relatives, pets, and anyone else who might find it interesting :)

UPD. Our competition will be generously sponsored by the TON Foundation, for which we are immensely grateful!

As a result, the following prizes will be awarded in the competition:

  • 1st place — 400 TON
  • 2nd place — 300 TON
  • 3rd place — 200 TON
  • 4th place — 100 TON

Additional prizes:

  • 1st place after the first day of the competition — 111 TON.
  • At the end of each minute of the competition, the current leader (provided there is at least one team with a positive score) receives 0.1 TON.
  • 300 TON will be distributed equally for the best solution of each test at the end of the competition. For example, if there are 10 tests, and Team A has the best result in the first three tests while Team B has the best result in the remaining seven, Team A will receive 300/10*3 = 90 TON, and Team B will receive 300/10*7 = 210 TON.

All ties are resolved by time — the team that achieves its result earlier ranks higher.

Thus, the total prize fund for the competition is over $10,000 at the current exchange rate.

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By Stefan2417, 4 weeks ago, translation, In English

Hello, Codeforces!

After a year of anticipation and several complete changes to the problem set, we are glad to invite you to take part in Codeforces Round 948 (Div. 2), which will start on Sunday, May/26/2024 17:35 (Moscow time). This round will be rated for participants whose rating is below 2100. Participants with higher ratings may participate out of the competition.

You will be given 5 problems and 2 hours to solve them. All the problems in the round are created and prepared by Stefan2417 and alexchist.

The round may include one or more interactive problems. Please read this blog to get familiar with this type of problems.

We would like to thank:

  • Vladithur for excellent round coordination!

Score distribution: $$$500 — 1250 — 1750 — 2000 — 2500$$$.

Your perception of the scoring may vary, so be sure to read the later problems if you get stuck on one.

Upd: Congratulations to the Winners!

Div 2:

  1. sun_gan_chou_yu_guan

  2. Maksiwelle

  3. suomynonA

  4. new_mistakes

  5. Kosyaaa

Div 1+2:

  1. tourist

  2. Sugar_fan

  3. sun_gan_chou_yu_guan

  4. abc864197532

  5. BurnedChicken

Upd: editorial

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By Bazoka13, 4 weeks ago, In English

Hello, Codeforces! Or, as we like to say in Servalish (created by Serval): High-low, Cold-for-seize!

We are glad to invite you to participate in Codeforces Round 947 (Div. 1 + Div. 2), which will start on May/25/2024 17:35 (Moscow time). The round is a combined round and will be rated for everyone.

The problems are prepared by Atomic-Jellyfish, Nerovix, SanweiTreap, Serval, Toxel, jhdonghj112 and me. You will be given 9 problems to solve in 3 hours. Scoring distribution will be announced later.

We would like to thank everyone that makes this round possible:

We recommend you to read the statements of all problems. Good luck & Have fun! (=・ω・=)

A no-prize quiz

UPD: Scoring distribution: 250-500-1000-1500-2000-2500-3000-4500-6000

UPD2: Editorial is available now.

UPD3: Thank you for your participation in this round! Congratulations to the winners:

  1. tourist
  2. Golovanov399
  3. maspy
  4. hos.lyric
  5. Um_nik

And the first solves on each problem:

UPD4: Chinese editorial is available now.

Photo of reviewer and some authors:

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By Temirulan, history, 4 weeks ago, In English

We invite you to first ICPC alumni event in Silicon Valley on June 4 at 6pm.

This is a unique event that will bring together top ICPC alumni and friends. The event will be attended by ICPC President Bill Poucher, Freedom Holding CEO Timur Turlov and Bagdat Mussin, President of the Kazakh Federation of Competitive Programming.

Register here:

P.S: wdyt about some small entertainy contest?

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By Vladosiya, history, 5 weeks ago, translation, In English

Hello! Codeforces Round 946 (Div. 3) will start at May/20/2024 17:35 (Moscow time). You will be offered 6-8 problems with expected difficulties to compose an interesting competition for participants with ratings up to 1600. However, all of you who wish to take part and have a rating of 1600 or higher, can register for the round unofficially.

The round will be hosted by rules of educational rounds (extended ICPC). Thus, solutions will be judged on preliminary tests during the round, and after the round, it will be a 12-hour phase of open hacks.

You will be given 7 problems and 2 hours and 15 minutes to solve them.

Note that the penalty for the wrong submission in this round 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 participant of the third division, you must:

  • take part in at least five 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.

Round is based on UKIEPC 2024: Spring Practice. Please refrain from participating in this round if you are familiar with the tasks of this competition.

I would like to thank:

  1. Authors of the original competition: Aksenov239, MaxBuzz, RobinFromTheHood, darnley, izban, pkhaustov, lsantire, az453, fedor.tsarev, Shoaib Jameel.

  2. MikeMirzayanov for help with ideas and Polygon and Codeforces platforms.

  3. -is-this-fft-, peltorator, tute7627 for red testing.

  4. senjougaharin, kaikey, gmusya, nskybytskyi, Giga_Cronos, diskoteka for yellow testing.

  5. TypeYippie, kzyKT, tepamid, ahshafi for purple testing.

  6. Abo_Samrah, Zandler, sam07a, YESMAKHAN, xygzy, Klaus26 for blue testing.

  7. Morvolzz, dasha..zhilina, sutekine, Muhsen, Gojova, Acanikolic73 for cyan testing.

  8. You for participation.

Good luck!

UPD: Editorial is out.

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By prvocislo, 5 weeks ago, In English

Ahoj, Codeforces!

We are excited to invite you to participate in Codeforces Round 945 (Div. 2), which will start on May/17/2024 17:35 (Moscow time).

The problems are authored by TimDee and prvocislo.

This round will be rated for participants whose rating is below $$$2100$$$. Participants with higher ratings are encouraged to participate out of the competition.

You will be given $$$6$$$ problems and $$$2$$$ hours to solve them. The scoring distribution is bellow. One of the problems will be interactive. Please read this blog to get familiar with this type of problems.

We would like to thank everyone, who made this round happen:

Scoring distribution: $$$500-1000-1500-2000-2250-3000$$$

Good luck, have fun and see you on Friday! ✩₊˚

Upd: Congratulations to the Winners!

Div 2:

1) _MyGO_Tomori_

2) Sxy_Limit

3) LofiGirl

4) prins

5) SXWZ-Queenie

Div 1+2:

1) BucketPotato with first AK!

2) gamegame

3) hitonanode

4) abc864197532

5) peti1234

Upd2: Editorial is out!

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By adamant, history, 5 weeks ago, In English

Hi everyone!

We organized an onsite competitive programming contest at ETH Zürich on May 11th, 2024. The contest is now uploaded to the Codeforces gym at ETH Zurich Competitive Programming Contest Spring 2024.

The onsite contest was 5h long and we recommend for you to participate in teams. In the onsite contest only one computer was allowed but participants could access the internet freely. The difficulty of the problemset is slightly easier than a regional ICPC contest but also offers a few hard problems. Difficulty range is from div2 A to div2 G.

Thanks a lot to all problem setters: BenniKartefla, Lakii, Lebossle, MihneaDAVID, OhLee, TecTrixer, ackj, adamant, alagorithmet and mango_lassi.

Additionally, a big thanks to all our testers and reviewers: Petr, Evirir, CSQ31, atakanysr, FatihSolak, qwexd, AhmetKaan, Macdu, atli164, SATSKY_2024target_IGM, SuprDewd, Tagl, Tobo, wildfire032, fried-chicken, theodor.moroianu and sischu74.

Tutorial Slides can be found here.

Congratulations to the top 5 of the onsite contest:

  1. mETHroners: GRT_2018, Meloric, paula
  2. Mr Malnars Lethal Peppers: pavkal5, DBradac, dpaleka
  3. uhh this should actually be first place, sorry, system error: AimShootReload, donentseto
  4. ML and AC: miguell, Andrei1998
  5. CrispyBeef: tiagodias, jonathanplsmith, Blackphoenyx

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