Vladosiya's blog

By Vladosiya, history, 17 months ago, translation, In English

Hello! Codeforces Round 834 (Div. 3) will start at Nov/18/2022 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 6-8 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.

Thanks to MikeMirzayanov for the platform, help with ideas for problems and for coordination of our work. Problems have been created and written by ITMO University team: MikeMirzayanov, myav, Gol_D, Aris, Gornak40, senjougaharin and Vladosiya.

We would like to thank: mumumucoder, Enkognit, orloffm, TeaTime, ilyamzy, Olympia, moonveil, 74TrAkToR, molney, elseecay, bigDuck, Nickir, Be_dos, OAleksa for testing the contest and valuable feedback. List of testers will be updated.

Good luck!

UPD: Editorial

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By Vladosiya, history, 19 months ago, translation, In English

1741A - Compare T-Shirt Sizes

Idea: MikeMirzayanov

Tutorial
Solution

1741B - Funny Permutation

Idea: MikeMirzayanov

Tutorial
Solution

1741C - Minimize the Thickness

Idea: MikeMirzayanov

Tutorial
Solution

1741D - Masha and a Beautiful Tree

Idea: Gornak40

Tutorial
Solution

1741E - Sending a Sequence Over the Network

Idea: MikeMirzayanov

Tutorial
Solution

1741F - Multi-Colored Segments

Idea: MikeMirzayanov, senjougaharin

Tutorial
Solution

1741G - Kirill and Company

Idea: Vladosiya

Tutorial
Solution

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By Vladosiya, history, 19 months ago, translation, In English

Hello! Codeforces Round 826 (Div. 3) will start at Oct/11/2022 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 6-8 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.

Thanks to MikeMirzayanov for the platform, help with ideas for problems and for coordination of our work. Problems have been created and written by ITMO University team: MikeMirzayanov, myav, Gol_D, Aris, Gornak40, senjougaharin and Vladosiya.

We would like to thank: Mangooste, Ormlis, oversolver, Be_dos, IzhtskiyTimofey, Stefan2417, ace5, BledDest, AbsurdMan, toxabuk, Kniaz, goncharovmike, YTatarin, pashka and great_fortune for testing the contest and valuable feedback. List of testers will be updated.

Good luck!

UPD: Editorial

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By Vladosiya, history, 19 months ago, translation, In English

1729A - Two Elevators

Idea: Vladosiya

Tutorial
Solution

1729B - Decode String

Idea: MikeMirzayanov

Tutorial
Solution

1729C - Jumping on Tiles

Idea: MikeMirzayanov, Aris

Tutorial
Solution

1729D - Friends and the Restaurant

Idea: MikeMirzayanov, Aris, myav

Tutorial
Solution

1729E - Guess the Cycle Size

Idea: Gornak40, MikeMirzayanov

Tutorial
Solution

1729F - Kirei and the Linear Function

Idea: Gornak40

Tutorial
Solution

1729G - Cut Substrings

Idea: senjougaharin, MikeMirzayanov

Tutorial
Solution

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By Vladosiya, history, 21 month(s) ago, In English

1714A - Everyone Loves to Sleep

Idea: Vladosiya

Tutorial
Solution

1714B - Remove Prefix

Idea: MikeMirzayanov

Tutorial
Solution

1714C - Minimum Varied Number

Idea: MikeMirzayanov

Tutorial
Solution

1714D - Color with Occurrences

Idea: MikeMirzayanov

Tutorial
Solution

1714E - Add Modulo 10

Idea: senjougaharin

Tutorial
Solution

1714F - Build a Tree and That Is It

Idea: MikeMirzayanov

Tutorial
Solution

1714G - Path Prefixes

Idea: MikeMirzayanov

Tutorial
Solution

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By Vladosiya, history, 21 month(s) ago, translation, In English

Hello! Codeforces Round 811 (Div. 3) will start at Aug/01/2022 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 ACM-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 6-8 problems and 2 hours and 15 minutes to solve them.

Note that the penalty for the wrong submission in this round (and the following Div. 3 rounds) 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.

Thanks to MikeMirzayanov for the platform, help with ideas for problems and for coordination of our work. Problems have been created and written by ITMO University teams: MikeMirzayanov, myav, Gol_D, Aris, senjougaharin, me Vladosiya.

Also many thanks to yorky, Jostic11, turmax, oversolver, ivanz, antonis.white, molney, KerakTelor, andrey.starodubtsev, Ahmad45123, myway, sofiaasta, Muhammad98 for testing the contest and valuable feedback.

Good luck!

UPD: Editorial

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By Vladosiya, history, 22 months ago, translation, In English

1702A - Round Down the Price

Idea: MikeMirzayanov

Tutorial
Solution

1702B - Polycarp Writes a String from Memory

Idea: MikeMirzayanov

Tutorial
Solution

1702C - Train and Queries

Idea: MikeMirzayanov

Tutorial
Solution

1702D - Not a Cheap String

Idea: MikeMirzayanov

Tutorial
Solution

1702E - Split Into Two Sets

Idea: MikeMirzayanov

Tutorial
Solution

1702F - Equate Multisets

Idea: MikeMirzayanov

Tutorial
Solution

1702G1 - Passable Paths (easy version)

Idea: MikeMirzayanov

Tutorial
Solution

1702G2 - Passable Paths (hard version)

Idea: MikeMirzayanov

Tutorial
Solution

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By Vladosiya, history, 23 months ago, translation, In English

Hello! Codeforces Round 797 (Div. 3) will start at Jun/07/2022 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 ACM-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 6-8 problems and 2 hours and 15 minutes to solve them.

Note that the penalty for the wrong submission in this round (and the following Div. 3 rounds) 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.

Thanks to MikeMirzayanov for the platform, help with ideas for problems and for coordination of our work. Problems have been created and written by ITMO University teams: MikeMirzayanov, MisterGu, myav, Gol_D, Aris, senjougaharin, me Vladosiya.

Also many thanks to Kirill22 , daubi , Fortin , Artem_Sukharev , vsinitsynav , yorky , oversolver , majorro , ilya_totl , Undying , olya.masaeva , Kniaz , Golovanov399 , farmerboy , Absyarka , Kavaliro , neeraj_joshi for testing the contest and valuable feedback.

Good luck!

UPD:Editorial

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By Vladosiya, history, 2 years ago, translation, In English

1675A - Еда для животных

Idea: MikeMirzayanov

Tutorial
Solution

1675B - Сделай возрастающую

Idea: MikeMirzayanov

Tutorial
Solution

1675C - Детективная задача

Idea: Gol_D

Tutorial
Solution

1675D - Вертикальные пути

Idea: MikeMirzayanov

Tutorial
Solution

1675E - Замени на предыдущий, минимизируй

Idea: myav

Tutorial
Solution

1675F - Влад и отложенные дела

Idea: Vladosiya

Tutorial
Solution

1675G - Сортировка блинчиков

Idea: Vladosiya

Tutorial
Solution

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By Vladosiya, history, 2 years ago, translation, In English

Hello! Codeforces Round 787 (Div. 3) will start at May/05/2022 17:35 (Moscow time). You will be offered 6-7 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 ACM-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 6-7 problems and 2 hours and 15 minutes to solve them.

Note that the penalty for the wrong submission in this round (and the following Div. 3 rounds) 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.

Thanks to MikeMirzayanov for the platform, help with ideas for problems and for coordination of our work. Problems have been created and written by ITMO University teams: MikeMirzayanov, MisterGu, myav, Gol_D, Aris, senjougaharin, me Vladosiya.

Also many thanks to avevad, yorky, UncleSema, vsinitsynav, GoracioNewport, Tvorozh0k, any_nickname, I.AM.THE.WILL and Jostic11 for testing the contest and valuable feedback.

Good luck!

UPD:Editorial

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By Vladosiya, history, 2 years ago, translation, In English

1650A - Deletions of Two Adjacent Letters

Idea: MikeMirzayanov

Tutorial
Solution

1650B - DIV + MOD

Idea: Vladosiya

Tutorial
Solution

1650C - Weight of the System of Nested Segments

Idea: myav

Tutorial
Solution

1650D - Twist the Permutation

Idea: MikeMirzayanov

Tutorial
Solution

1650E - Rescheduling the Exam

Idea: senjougaharin

Tutorial
Solution

1650F - Vitaly and Advanced Useless Algorithms

Idea: Aris

Tutorial
Solution

1650G - Counting Shortcuts

Idea: MikeMirzayanov

Tutorial
Solution

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By Vladosiya, history, 2 years ago, translation, In English

Hello! Codeforces Round 776 (Div. 3) will start at Mar/08/2022 17:35 (Moscow time). You will be offered 7-8 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 ACM-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 7-8 problems and 2 hours and 15 minutes to solve them.

Note that the penalty for the wrong submission in this round (and the following Div. 3 rounds) 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.

Thanks to MikeMirzayanov for the platform, help with ideas for problems and for coordination of our work. Problems have been created and written by ITMO University teams: MikeMirzayanov, MisterGu, myav, Gol_D, Aris, senjougaharin, me Vladosiya.

Also many thanks to mango_lassi, espr1t, karemo, starboy_jb, Fly_37, omikad, Katya_Goryachkina, Omja, teraqqq, oversolver, Jostic11, yorky, _4dr_ and doreshnikov for testing the contest and valuable feedback.

Good luck!

UPD: Congratulations girls on International Women's Day <3.

UPD 2: Editorial

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By Vladosiya, history, 2 years ago, translation, In English

1624A - Plus One on the Subset

Idea: MikeMirzayanov

Tutorial
Solution

1624B - Make AP

Idea: senjougaharin

Tutorial
Solution

1624C - Division by Two and Permutation

Idea: MikeMirzayanov

Tutorial
Solution

1624D - Palindromes Coloring

Idea: senjougaharin

Tutorial
Solution

1624E - Masha-forgetful

Idea: Aris

Tutorial
Solution

1624F - Interacdive Problem

Idea: Vladosiya

Tutorial
Solution

1624G - MinOr Tree

Idea: Vladosiya

Tutorial
Solution

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By Vladosiya, 2 years ago, translation, In English

Hello! Codeforces Round 762 (Div. 3) will start at Dec/20/2021 17:35 (Moscow time). You will be offered 7-8 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 ACM-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 7-8 problems and 2 hours and 15 minutes to solve them.

Note that the penalty for the wrong submission in this round (and the following Div. 3 rounds) 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.

Thanks to MikeMirzayanov for the platform, help with ideas for problems and for coordination of our work. Problems have been created and written by ITMO University teams: MikeMirzayanov, MisterGu, myav, Gol_D, Aris, senjougaharin, me Vladosiya and SGU student Brovko.

Also many thanks to Geothermal, Rafbill, Sugar_fan, mango_lassi, hitonanode, Resende, Igorjan94, CtrlAlt, KerakTelor, FlakeLCR, MatheusMonteiro, Loolo, kocko for testing the contest and valuable feedback.

Good luck!

UPD 1: The opinion of the testers about the order of problems turned out to be so heterogeneous that there is no way to be sure about the increase in the complexity of problems in the set. We advise you to read all problems.

UPD 2: If you are a schoolchild from the Saratov region, then please refrain from participating in the round. One of the problems may be familiar to you. Thanks!

UPD 3: Editorial

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