BlueSmoke's blog

By BlueSmoke, 5 years ago, In English

You can view Chinese editorial here: https://www.luogu.com.cn/blog/Caro23333/codeforces-round-641-zhong-wen-ti-xie

Div2.A Problem and editorial by BlueSmoke

Editorial
Code

Div2.B Problem and editorial by BlueSmoke

Editorial
Code

Div1.A Problem and editorial by mydiplomacy

Editorial
Code

Div1.B Problem and editorial by A.K.E.E.

Editorial
Code

Div1.C Problem and editorial by A.K.E.E.

Editorial
Code

Div1.D Problem and editorial by Rebelz

Part of solution by Elegia

Editorial
Code

Div1.E Problem and editorial by A.K.E.E.

Editorial
Code

Div1.F Problem and editorial by Rebelz

Hard version solution by Elegia

Editorial for easy version
Code
Editorial for hard version
Code

You can also view Div1.F editorial by Elegia here: https://codeforces.net/blog/entry/77280

Anyway, hope you like these problems and thank you for participating!

Full text and comments »

  • Vote: I like it
  • +296
  • Vote: I do not like it

By BlueSmoke, 5 years ago, In English

Hello, Codeforces!

We are excited to invite you to Codeforces Round 641 (Div. 1) and Codeforces Round 641 (Div. 2). This round will take place on May/12/2020 15:35 (Moscow time). In both divisions, you will have 2.5 hours to solve 6 problems. Please notice the unusual time.

Problems of this round were prepared by Rebelz, A.K.E.E., mydiplomacy and me BlueSmoke.

We would like to express our sincere gratitude to:

We have made an effort to create interesting problems, strong tests and clear statements. Wish all of you good luck and have fun! Since the round is rated, we also wish you guys have huge positive $$$\Delta$$$ in this round!

UPD: Tester list updated.

UPD: Tester list is updated again. Apart from that, score distribution is here:

  • Div.1: $$$500+1250+1250+2000+2500+(1750+1750)$$$

  • Div.2: $$$500+1000+1500+2250+2250+3000$$$

UPD: Hey, it seems that Div.1 is really hard and has bad discrimination. And also, in some problems pretests are weak. We are sorry about our mistakes, and hope you will like these problems after reading editorials here: https://codeforces.net/blog/entry/77284

UPD: Congratulations to the winners!

Div.1:

Div.2:

Hope you have a nice day! Also you can view a blog by our tester Hazyknight about his opinions of this round: https://codeforces.net/blog/entry/77276

Full text and comments »

  • Vote: I like it
  • +940
  • Vote: I do not like it