Hi Everyone,

We are excited to announce that we will be having the following sessions on Algoplanet:

1) Square root decomposition and related problem solving by maomao90 on 22nd September(12pm UTC/5.30pm IST)

2) I will be taking a session on game theory(nim game,grundy numbers and the sprague grundy thereom) and related problem solving at 12.30pm UTC/6pm IST on 25th.Will also be covering proofs of the same.

3) Binary lifting,Lowest Common Ancestor and related problem solving by PoPularPlusPlus on 29th at 3pm UTC/8.30pm IST

You can get more information by joining the discord server by just filling this form (800+ members)

Recording will also be uploaded to the algoplanet youtube channel

Update:timing of class on 25th has been changed due to the CF contest.The class on 28th is also shifted to 29th

Part-1 of Square root Decomposition has been uploaded to youtube here

Part 2 and 3 will be uploaded soon.

Update 2 Square Root Decomposition Part-2 and Part-3

Advanced Game Theory

Introduction to Binary Lifting and Lowest Common Ancestor

Update:2 new videos have been uploaded:

1. Some Interesting Problems(Adhoc,Data Structures and Graphs)
2. DP Optimizations Part-2(dnc,knuth,1d1d)

Hi Codeforces,

I started Algoplanet,a club for competitive programming a few months back.It is an initiative for providing mentorship and guidance to passionate competitive programmers.

You can check the Algoplanet Youtube channel here

Recently we have uploaded videos on the following topics:

1) Convex Hull Trick(DP optimization) by sidhant

2) Heavy Light Decomposition and related problem by kshitij_sodani

We have also done some problem solving sessions before(1 2). There are regular mashup contests and problemsets are also provided.

You can get updated about future activities by joining the discord server (700+ members)

Edit: I have uploaded a new video: Problem Solving Session(Atcoder problems)

Hi All,
I am starting Algoplanet,a club for competitive programming.It is an initiative for providing mentorship and guidance to passionate competitive programmers.

We will help you in the following ways:

• We will be hosting sessions for teaching new techniques and will also be discussing interesting problems.
• Regular Mashup contests will be conducted and weekly problemsets will be given.
• Providing hints to solve problems in practice
• You can improve your problem solving abilities and also find a like-minded community to discuss problems.

It is open for all and is completely free of cost.

Please fill this form if you wish to join Algoplanet. The group will be on discord.

Looking forward to see you all there.

Update:Emails have been sent a few hours ago to those who filled the form.Please check Spam if you haven't received.Later registrations will be processed in a rolling basis.

Update 2: I have also started a youtube channel. The group has also crossed 450 members now.

Hi ICPC Gwalior-Pune Contestants, We are provisionally releasing the ranklist subject to plag checks. Congratulations to all the winners and hope you enjoyed the contest.

1. IIT- Bombay; TheOneYouWant BhaskarTM Shivam_18
2. IIT Guwahati- EnEm zeus_iitg BrownieTK
3. IIT Madras- Kira_1234 KDVinit rtzrtz
4. IIT Kanpur; aryanc403 umang99m _Aaryan_
5. IIT Kharagpur ; cheems bhagwa_brigade RahulChugh

Pass-the-message,House Hunting and La La Langton's Ant problems Remained unsolved in the contest.Shinobu had 1 AC and Wakka and Molly had 2 AC.Top team solved 7 problems.

The full scoreboard is available at https://codedrills.io/contests/icpc-gwalior-pune-2020-regional-round/scoreboard

Hello everyone!

T1duS, Ashishgup,xennygrimmato and I will be capturing the live updates of the Gwalior-Pune 2020 Regionals, for teams to later refer to first-solves and the state of ranklist after various times. It is inspired by similar blogs in the past, like this, for example.

Important Information:

• Rank List (Scoreboard): https://codedrills.io/contests/icpc-gwalior-pune-2020-regional-round/scoreboard
• Contest Page: https://codedrills.io/contests/icpc-gwalior-pune-2020-regional-round
• Contest Blog: https://codeforces.net/blog/entry/93980
• Contest Duration: 4 hours.
• Tentative Start Time: 18:00 IST

Announcements:

• All problems have a memory limit of 1GB, and solutions that exceed this would be marked as RTE instead of MLE due to some memory usage issues.

Live Updates:

• 6.06pm: Treap Trilogy from BITS-Pilani, Goa Campus gets the first AC of the contest on the problem Jeff
• 6.15pm: Jeff is now solved by 112 teams,Vichitrödinger's Cat by 13 teams and Apple Uniformity by 9 teams.
• 6.23pm: Problem A gets its first AC
• 6.27pm: Hold right there Sparky!! from IIT Roorkee is the first team to solve 4 problems.
• 6.29pm: Sheesh! from IIT Jodhpur gets 2 ACs within 30 seconds to lead the scoreboard!
• 6.40pm: Cheese_Maggi from IIT Guwahati gets first AC on Dimitrescu
• 6.51pm: 473 teams have now solved at least 1 problem in the contest.
• 7.03pm: Cheese_Maggi from IIT Guwahati Takes the lead by solving 5 problems.

• 7.35pm : The top 9 teams have solved 5 problems each. The top 2 teams are separated by 8 minutes of time penalty.
• 7.38pm: Cheese_Maggi solve their 6th problem and move up to the top of the scoreboard.
• 7.58pm: Cheese_Maggi still lead, followed by 23 teams with 5 problems solved.
• 8.24pm: Evil Geniuses from IIT Madras move up to Rank #2 after solving Fermod. Cheese_Maggi continue to lead with a 90-minute time-penalty lead.
• 8.40pm KuchBhiRandom from IIT Kanpur also solve their 6th problem
• 9.00pm Scoreboard has freezed

Hi ICPC Amritapuri Contestants, It was originally planned to release the ranklist at the ceremony on 21st August, Saturday. However we got some feedback from the contestants that it will be important to know the ranks before other regionals. After discussions between the setting team and the RCD, we have decided to provisionally release the ranklist subject to plag checks. The solution discussion and award ceremony will still be on 21st August. Congratulations to the winners and hope you enjoyed the contest.

1. IIT- Roorkee — amnesiac_dusk buri_buri_zaemon_ harshhx17
2. IIT Kanpur- Dragnoid99 mohanraghug abhinavvv306
3. DA-IICT- nishant403 Jaydeep999997 harshrajani460
4. IIIT Hyderabad — gaurav172 shaanknight vivace_jr
5. Bits Pilani — Lain geckods lolok123

Cat and Dice problem Remained unsolved in the contest.Cubical had 1 AC and Lag had 3 AC.Top team solved 8 problems,4 teams got 7 problems and 10 teams got 6 problems.

https://codedrills.io/contests/icpc-amritapuri-2020-regional-round/scoreboard

Hi Codeforces!

ICPC Amritapuri 2020 Regional Round will be held on Codedrills tomorrow.

Contest Details

• Contest Link — ICPC Amritapuri 2020 Regional Round
• Date & Time — 14 August 2021, Saturday, 18:00 IST
• Duration — 4 Hours
• There is a ranklist freeze of 60 minutes. Ranklist will freeze at 21:00 IST.
• There will be 10-13 problems to solve
• Will follow standard ICPC scoring system (20 minutes penalty and 1 point per problem)
• The problems may not be sorted by difficulty

Selection Criteria

• Top few teams will advance to World Finals

Clarifications

• Only ask the clarifications about the problems by messaging the private clarification group via discuss.
• Do not ask any doubts about the problems on this blog till the contest ends.

Good luck Have Fun! Hope you like the problems!

You can find the live updates here

Credits:

• Chief Judge: Balajiganapathi Balajiganapathi S
• Contest Admin: Vichitr Vichitr Gandas
• Setters:
  • Kevin kevinsogo Charles Atienza(Set 7 problems!), Ajinkya ajinkya1p3 Parab
  • Vichitr Vichitr Gandas ,Vaibhav xennygrimmato Tulsyan
• Testers:
  • Kshitij kshitij_sodani Sodani ,Udit T1duS Sanghi(Total combined testing of all the problems!)
  • Ashish Ashishgup Gupta ,Varad playing_it_my_way Kulkarni, Aswin aswinashok44 Ashok
  • Mayank katana_handler Pugalia, Daanish 7dan Mahajan,Ritul ritul_kr_singh Singh , Divyansh failed_coder Verma
  • Soumyaditya socho Choudhuri ,Naveen mnaveenkumar2009 Kumar, Het hetshah1998 Shah, Saarang saarang Srinivasan
  • Setters,Chief Judge and Contest Admin
• Platform Coordinator: Deepa deepa_panwar Panwar
• RCD: Maheshwara anandoham Chaitanya

I have made this blog to add links and information of all oi contest(official contest/mirror) happening this year.I missed out the official contests of IZHO and infocup(didn't come to know and no blog post on cf as well).Please post a comment if you know any other OI contest with contest date/registeration date or link

JOI final round- https://contests.ioi-jp.org/joi-ho-2021/index-en.html
toki cms contest- https://codeforces.net/blog/entry/85545
Finnish Olympiad in Informatics- https://codeforces.net/blog/entry/87261
EGOI 2021 : https://egoi.ch/en/
infocup- https://www.info1cup.com/#schedule
COCI- https://hsin.hr/coci/
usaco- http://www.usaco.org/
APIO 2021- https://apio2021.id/
IOI 2021- https://ioi2021.sg/
Innopolis Open Olympiad in Informatics(finals on 21st February)- https://codeforces.net/blog/entry/84596 CEOI 2021- https://hsin.hr/ceoi/
IZHO 2021- https://izho.kz/izho-2021/about/
BOI(Baltic) 2021- https://bwinf.de/olympiade/boi2021/

http://www.boi2020.lv/
According to this site the official competition will be held online from 20th-22nd July. I am curious to know if there will be a mirror contest.

Also what is the status of other contests like JOIOC,COI,CEOI,balkan etc? Want to know because these contests are very good to practice for TST and IOI