MagentaCobra's blog

By MagentaCobra, 3 years ago, In English

Hi all!

This weekend, at Oct/17/2021 14:05 (Moscow time) we will hold Codeforces Round 749 (Div. 1 + Div. 2, based on Technocup 2022 Elimination Round 1). It is based on the problems of Technocup 2022 Elimination Round 1 that will be held at the same time.

Note the unusual start time of the contest.

Technocup is a major olympiad for Russian-speaking high-school students, so if you fall into this category, please register at Technocup website and take part in the Elimination Round.

The Div. 1 + Div.2 edition is open and rated for everyone. Register and enjoy the contests!

The problems were written and prepared by Tlatoani, golions, rabaiBomkarBittalBang, qlf9, and me. We would like to express our thanks for antontrygubO_o, isaf27, and KAN for reviewing our problems and being great coordinators!

Huge thanks to the following users for testing our round: 244mhq, AmShZ, dorijanlendvaj, Keshi, czhang2718, 2020akadaver, Magikarp1, Richw818, quantum8, RayLee234, SlavicG, Qualified, Monogon, smax, wxhtzdy, kassutta, namanbansal013, HackerMonk, Ari, PurpleCrayon, FieryPhoenix, Jellyman102, bWayne, H4ckOm, Aleks5d, Makcum888

And as usual, thanks to MikeMirzayanov for the great Codeforces and Polygon platforms.

You will have 2 hours and 15 minutes to solve 9 problems. The score distribution will be announced very shortly before the contest starts. Good luck to all!

UPD1:

Score distribution: $$$500$$$ — $$$1000$$$ — $$$1500$$$ — $$$1750$$$ — $$$2250$$$ — $$$2750$$$ — $$$3000$$$ — $$$3500$$$ — $$$4000$$$.

UPD2:

Thanks to everyone who participated in the contest! We hope you enjoyed the problems. We apologize for the issues at the beginning of the contest; we hope that you were still able to have a great experience.

Editorial

UPD3:

Congratulations to the winners of Codeforces Round 749 (Div. 1 + Div. 2, based on Technocup 2022 Elimination Round 1)!

  1. nutella_waxberry
  2. fivedemands
  3. jiangly
  4. peti1234
  5. xay5421
  6. Um_nik
  7. orzdevinwang
  8. yosupo
  9. SHZhang
  10. tatyam

And a special congratulations to peti1234 for being the only contestant to solve problem I!

Congratulations also to the winners of Technocup 2022 - Elimination Round 1!

  1. Ormlis
  2. SomethingNew
  3. Arayi
  4. alexxela12345
  5. I_HATE_CONSTRUCTIVES
  6. oleh1421
  7. Mangooste
  8. arbuzick
  9. idontwannawin
  10. Dasha_Gnedko

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By MagentaCobra, history, 4 years ago, In English

So today I struggled to solve 1527B2 - Palindrome Game (hard version) officially today. I ended up getting wa tc 2, which seems pretty common at first. However, after the contest finished, I noticed that the ONLY reason why my solution wasn't correct was because I said "TIE" instead of "DRAW"

116825145 (The WA officially) 116845616 (AC after the contest)

I don't understand why problem writers can't spend time to include complete samples? I've written a few official CF rounds myself, and this is definitely not OK. Samples should always include all possible types of output. You can't argue the case that not including a "DRAW" case in samples will give away the problem either, because it clearly doesn't (001 is a trivial "DRAW" case).

Please do better next time. I'm super disappointed that none of the problem writers, the coordinator, or even any of the testers pointed this out. We look forward to these contests every time they happen, and it really sucks when your performance is ruined by a silly thing like this.

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By MagentaCobra, 4 years ago, In English

Obviously, do not discuss problems until after the contest is over. Good luck to everyone competing today, especially to my fellow UVA teams! :D

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By MagentaCobra, history, 4 years ago, In English

We really hope you enjoyed the problems! We apologize again for the long queue and unrated round. Just for fun, here's how many of our problems were rejected:

Rejection Count
Tutorial is loading...

Solution: 86603804

Idea: MagentaCobra

Preparation: MagentaCobra, qlf9

Tutorial is loading...
Solution: 86603838

Idea: qlf9

Preparation: qlf9

Tutorial is loading...
Solution: 86603857

Idea: MagentaCobra

Preparation: MagentaCobra, qlf9

Tutorial is loading...
Solution: 86603878

Idea: MagentaCobra

Preparation: MagentaCobra, Tlatoani

Tutorial is loading...
Solution: 86603896

Idea: golions

Preparation: Tlatoani, golions

Tutorial is loading...
Solution 1: 86603917

Solution 2: 86603930

Idea: golions

Preparation: Tlatoani, golions

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By MagentaCobra, 4 years ago, In English

Hey everybody!

We (MagentaCobra, Tlatoani, golions, qlf9) are super excited to invite you to take part in Codeforces Round 655 (Div. 2), which will happen on Jul/11/2020 18:05 (Moscow time). Please note the unusual start time. The round is rated for users with rating strictly less than 2100, although higher rated users are more than welcome to take part out of competition.

Huge thanks to those who helped make this round possible:

There will be 6 problems and 2 hours to solve them.

We really hope you enjoy our first contest!

UPD: Scoring Distribution:

500—1000—1500—2000—2500—3000

UPD: Due to long queue, the round will be unrated. We're extremely sorry this happened, and all of us are sad about it. We hope you will at least enjoy the problems.

UPD: Editorial

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By MagentaCobra, history, 5 years ago, In English

How much did you improve over the past year? What are your goals for Codeforces/CP in general for the new decade?

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