Ari's blog

By Ari, history, 5 weeks ago, In English

Note: I can't figure out how to place the tutorials inside spoilers. If someone is familiar with how CF spoilers work and can help I would really appreciate it. For now, be warned that the tutorials are visible by default (but everything else isn't)

UPD: I figured out how to use spoilers! Also added implementations for all problems.

Thanks for participating in our contest!

1509A - Средняя высота

Author: Kuroni
First solve: cfg0d at 00:01:02

Hint
Tutorial
Comments from the authors

Implementation

1509B - ТМТ документ

Author: Ari
First solve: blue5002 at 00:04:51

Hint
Tutorial
Comments from the authors

Implementation

1509C - Спортивный фестиваль

Author: Ari
First solve: Dukkha at 00:05:32

Hint 1
Hint 2
Tutorial
Comments from the authors

Implementation

1508A - Бинарная литература

Author: Ari
First solve (Div. 2): traxex2 at 00:22:48
First solve (Div. 1): tourist at 00:05:04

Hint 1
Hint 2
Hint 3
Tutorial
Comments from the authors

Implementation

1508B - Почти отсортированные

Author: Both of us!
First solve (Div. 2): shenmadongdong.qaq at 00:29:52
First solve (Div. 1): tourist at 00:08:19

Hint 1
Hint 2
Hint 3
Tutorial
Comments from the authors

Implementation

1508C - Завершите MST

Author: Kuroni
First solve (Div. 2): deepspacewaifu at 01:42:36
First solve (Div. 1): maroonrk at 00:33:17

Hint 1
Hint 2
Hint 3
Hint 4
Tutorial
Comments from the authors

Implementation

1508D - Обмены на ребрах

Author: Ari
First solve: ksun48 at 00:57:13

Hint 1
Hint 2
Hint 3
Hint 4
Tutorial
Comments from the authors

Implementation

1508E - Дерево-календарь

Author: Kuroni
First solve: ecnerwala at 01:02:26

Hint 1
Hint 2
Hint 3
Hint 4
Tutorial
Comments from the authors

Implementation

1508F - Оптимальное кодирование

Author: Kuroni
First solve: ecnerwala at 01:52:02 (The only contestant who solved this problem!)

Hint 1
Hint 2
Hint 3
Hint 4
Hint 5
Hint 6
Tutorial
Comments from the authors

Implementation

Finally, here's some funny moments that happened while we were working on the round :)

Memes

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By Ari, history, 4 months ago, In English

Hello friends! I was inspired by the recent logo change to make a new logo for codeforces, just for fun. The link to check it out is below, all feedback is appreciated!

Edit: Just a little side note for those unfamiliar with imgur: You can click the link to see the image

https://i.imgur.com/vUCQVjE.png

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By Ari, 11 months ago, In English

Hi!

On Jul/04/2020 17:45 (Moscow time) we will host Codeforces Global Round 9.

It is the third round of a 2020 series of Codeforces Global Rounds. The rounds are open and rated for everybody.

The prizes for this round:

  • 30 best participants get a t-shirt.
  • 20 t-shirts are randomly distributed among those with ranks between 31 and 500, inclusive.

The prizes for the 6-round series in 2020:

  • In each round top-100 participants get points according to the table.
  • The final result for each participant is equal to the sum of points he gets in the four rounds he placed the highest.
  • The best 20 participants over all series get sweatshirts and place certificates.

Thanks to XTX, which in 2020 supported the global rounds initiative!

The problems of this round were prepared by a team of authors: adamant, antontrygubO_o, Ari, dengyaotriangle, hugopm, Kuroni, MrDecomposition, and Ynoi. We would like to thank the following people:

You will be given 2 hours and 30 minutes to solve 9 problems, and we highly encourage you to read all of them :)

To save testers the work of writing their opinion in the comments, we have compiled some of their opinions for them!

Round Feedback

Good luck!

UPD: Score distribution:

500 — 750 — 1500 — 1750 — 2000 — 2000 — 2250 — 2750 — 4000

UPD2: Editorial

UPD3: System tests have finished, congratulations to the winners!

  1. tourist
  2. scott_wu
  3. yosupo
  4. Um_nik
  5. Miracle03
  6. lqs2015
  7. heno239
  8. Motarack
  9. zeronumber
  10. Itst_boyfriend

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Announcement of Codeforces Global Round 9
 
 
 
 
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By Ari, history, 2 years ago, In English

Thank you for participating! We hope you liked our problems.

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By Ari, history, 2 years ago, In English

Hi Codeforces!

We are happy to invite you to take part in Codeforces Round #561 (Div. 2). The contest will be held on May/17/2019 18:05 (Moscow time).

You will be given 6 problems and 2 hours to solve them. The round will be rated for all contestants with rating below 2100. As usual, participants from the first division are welcome to join out of competition.

The problems were written and prepared by Jefe and me. We owe a huge thanks to KAN for coordinating the round, to Lewin and mohammedehab2002 for testing, and of course, to MikeMirzayanov for the great Codeforces and Polygon platforms.

Good luck and have fun!

UPD: A huge thanks to neal, dreamoon_love_AA, and antguz for help with additional testing.

UPD2: Thanks for participating! System tests have finished. Congratulations to our winners!

Div. 2

  1. thuytrang12a2

  2. Sigyn

  3. HaylayWilliams

  4. albertg

  5. Tianhen

Div. 1 + Div. 2:

  1. kefaa2

  2. Um_nik

  3. uwi

  4. thuytrang12a2

  5. HIR180

Editorial will be available soon.

UPD3: Editorial is up!

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