FelixArg's blog

By FelixArg, history, 5 days ago, translation, In English

Thank you for participating! I hope you enjoyed the tasks.

One of the testers (redpanda) did a wonderful video analysis tasks A-C, I highly recommend watching it.

1982A - Soccer

Tutorial
Solution (74TrAkToR)

1982B - Collatz Conjecture

Tutorial
Solution (FelixArg)

1982C - Boring Day

Hint 1
Hint 2
Tutorial
Solution 1 (FelixArg)
Solution 2 (74TrAkToR)

1982D - Beauty of the mountains

Hint 1
Hint 2
Tutorial
Solution (FelixArg)

1982E - Number of k-good subarrays

Hint
Tutorial
Solution (FelixArg)

1982F - Sorting Problem Again

Hint
Tutorial
Solution (FelixArg)

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By FelixArg, history, 9 days ago, translation, In English

Hello, Codeforces!

It's been a long journey, and I'm finally pleased to invite you to participate in our Codeforces Round 955 (Div. 2, with prizes from NEAR!), which will take place on Jun/25/2024 17:35 (Moscow time).

This round will be rated for all participants with a rating is below 2100. Participants with higher ratings can participate out of competition.

During the round, you will need to solve 6 problems. You will have 2 hours to solve them.

The problems for the round were prepared by nik1998, egor4444ik, iamdimonis and me.

We sincerely thank everyone who provided invaluable assistance in preparing this round:

We are pleased to announce that NEAR has supported the round!

NEAR was founded in 2017 by Illia Polosukhin, one of the creators of Transformers, and Alex Skidanov as an attempt to build an artificial system capable of solving competitive programming problems. You can read more about that attempt here.

Ultimately, NEAR pivoted into building a blockchain protocol, which it launched in 2020.

This year, NEAR started NEAR.AI, a new lab with a mission to build AI systems that are open and available to everyone, instead of being controlled by a few mega-corporations.

One of the areas of focus is making models capable of reasoning reliably, and for that, competitive programming problems provide a great environment. To help us build it, we invite all the Russian-speaking members of the Codeforces community with a rating of Specialist or higher (1400+) to help us annotate step-by-step explanations of solutions to competitive programming problems. We want to annotate a very large set of problems of all difficulty levels, and pay relatively high rewards in NEAR per annotation. Don't speak Russian but speak English? Stay tuned here, we will be launching the same project for English-speaking people very soon, and will likely sponsor another round when it happens.

The round also features prizes in NEAR. Participants who rank in the top 16 will receive Ⓝ 16 each. The next 32 participants in the overall ranking (including unofficial participants) will receive Ⓝ 8 each. The following 64 participants will receive Ⓝ 4 each; the subsequent 128 participants will receive Ⓝ 2 each, and finally, the next 256 participants will receive Ⓝ 1 each.

Additionally, 64 random participants from the top 4096 in the overall ranking will each receive Ⓝ 4.

Score distribution: $$$500\,—\,1000\,—\,1000\,—\,1750\,—\,2500\,—\,3000$$$

Wishing everyone good luck and high ratings!

UPD: Let's continue the series of announcements with a photo of the authors :)

UPD 2: Editorial!

UPD 3: Congratulations to the winners!

Div 1:

  1. tourist

  2. jiangly

  3. SSerxhs

  4. kizen

  5. potato167

Div 2:

  1. lunchbox

  2. _JiaY19_

  3. gxy001

  4. _DongY19_

  5. Muelsyse_sep005

UPD 4: Wonderful video analysis of A-E tasks. Thank you, Shayan!

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