Hello Codeforces community,

CodeChef is delighted to announce the 3rd edition of ICPC for Schools conducted in collaboration with Amrita School of Engineering, Coimbatore and ABV-IIITM Gwalior. This initiative was conceived in 2016 by CodeChef in association with Amrita University, Kollam.

This post is primarily directed towards the students studying in Indian schools.

About

ICPC for Schools is an opportunity for school teams to participate in ICPC regionals competing along with the best college teams from across India.

It aims to encourage school students to take up competitive programming and improving their algorithmic programming skills early in school. School teams will be participating alongwith the college teams, competing with them as well.

Format Of The Competition

The competition consists of two rounds.

Online round (Eliminations)

Date: 23rd October 2018 (Tue)
Timing: Yet to be announced
Contest link: www.codechef.com/ACMIND18

Onsite regional round (Finals)

After the online round, those teams who solve atleast one problem in the online round, will have to select at most 2 regional sites. Based on the team’s site selection, performance in the online round and number of slots at each regional site, it will be allotted regional site(s).
Dates:

• ABV-IIITM Gwalior: 16-17 December 2018
• Amrita School of Engineering Coimbatore: 28-29 December 2018

Certificates And Prizes

• All the teams solving at least one problem in the online round are eligible to receive a participation certificate.
• All the teams attending the regional round will receive a participation certificate and ICPC — CodeChef goodies
• The top team(s)* at each regional site, wins a cash prize, up to INR 20,000.
• Jackpot prize: If a team comes in the top 12% in the onsite regional rank-list among the college and school students, then they get double the eligible cash prize.
• *Exact distribution will be announced after the online round results based on the participation and the number of slots at each regional site.

Registration

• Register your team here: www.codechef.com/teams/register/ICPCSC18
• Last date to register: 21 October, 2018
• There is no registration fee for the online round
• You can participate if you are studying in a school in India
• A team can have up to 3 members. Even a single member can compete as a team.
• No participant can be a member of more than one team.

The details of the contest as a whole: timings, contest format and the prizes; can be found here.

Hello Codeforces community,

I am pleased to invite you all for ICO Preparatory Contest #1 held on 20th July, 2018.

The setting panel for this time includes-

Problem Setter(s): AsleepAdhyyan, ista2000
Problem Tester(s): AsleepAdhyyan, ista2000
Editorialist: vijju123

The contest is unrated for both divisions. Its not much that we get to participating without rating-stress in a contest. :)
The problems are going to be pretty easy.(Somewhere between division 2 and 3). So, this is a beginner friendly contest, specially those who are training for IOI. There are going to be detailed editorials.

The official details are-

Date: 20th July,2018.
Time: 7:00 PM to 11:00 PM IST (i.e. 19:00 to 23:00 IST)
Contest link: https://www.codechef.com/ICOP1901
Number of Problems: 4 problems.

Wish you all the best and hope to see your participation on 20th. :)

Hello Codeforces community,

I am so happy that I could finally understand segment tree beats good enough make a video tutorial on it. I tried to make it as simple as possible. Please do give me some feedback. positive or negative or ask if there is any ambiguity or query.

I had made a video on centroid decomposition(It's there in the same channel) which has received a lot of positive feedback, thank you all! I had planned to make more videos but I stopped because of busy school. I am now free from school for a few months now and would like to make more videos on hard topics, I may stop uploading if I get busy again. So, I request you all to suggest me some topics. :D I will try my best to make a video on them.

I really hope you all like it as it took me about 20 hours of direct and a week of indirect work to make this video with minimal equipment. If you finally understood this topic and commented, my goal would be accomplished. :D

This video is intended to be contributed to my school club but the video is public so anyone can benefit from it.

There might be unintended errors in whatever I have written and also the subtitles, please do notify me if you find anything like that. :D

And lastly, ignore if you can hear birds chirping and other background noises, I will try my best to improve the quality in my next videos. :)

Link: https://youtu.be/UJyBHCXa-1g
Enjoy! :D

UPDATE: I am a minutephysics fan so I like his style and incorporated into my videos too. Do comment on that as well, will help me get a better view on which style is the best. :D

Hello,

I have tried cloning a previous codeforces contest to hold a private contest but I cannot access the standings, I get the Error page("All your bugs are belong to me."). The standings are available if I create a mashup and add problems one by one. Is this a "feature" of cloning the contests or is this a bug?

P.S. I am sorry if this has been asked before, I tried to google but couldn't find any results.

UPDATE: Just noticed that even problemset page and contest pages give the same error. But the problem with cloning contests isn't related to this because I have experienced it quite some time ago(Last week to be exact), and it still persists.

Hello wonderful Codeforces Community!

I would like to invite you to the 6th and the last contest of the Preparatory Series for the Indian Computing Olympiad hosted by us. The contest will start on 4th Januray, 2018 7:30 PM IST.



The problems are set by Adhyyan Sekhsaria(AsleepAdhyyan), Soham Mukherjee(antipr000) and me(ista2000). I would also like to thank Taranpreet Singh(taran_1407) to help us with the testing and editorials. :D

There will be 4 problems and 3 hours to solve them. The difficulty will be around the INOI level although anyone can participate for the joy of solving the problems. :D

Contest link: Click here

I hope you like the problems and this serves as a great start to the year. :)

All the best, see you on the leaderboards. :D

Can someone please help me understand what does this error message say in my submission to problem A in today's contest (Round 407 div2)? Link here.

This proves that you can solve a single problem in infinite ways(Or at least 4). Problem: 630A - Опять двадцать пять!

I need a bit of help in the problem 456E - Civilization. This is my submission: 25396119. I don't understand where I went wrong because the test case is very big. Please help me figure out the mistake in my solution. Thank you in advance for your help :)

I have recently subscribed to a telegram bot that sends me messages for the future contests on codeforces, codechef and topcoder.

I found some contests which don't appear on the "Contest" tab but showing that they will start in a day or an hour. And also I cant register for those. What are they? The links to the contests are below:
http://mirror.codeforces.com/contests/769
http://mirror.codeforces.com/contests/780

Hello Codeforces,

As said in my last blog post on Codeforces, I have crated a blog and also made my first post. I also added some nice features(Check out the side bar ;)). Its mainly aimed for beginner programmers for now, as I am not as good myself, but I will improve the quality of post overtime. Please, check out my blog and give me suggestions on what should I post about, any improvements and so on. Your feedback will be invaluable for me. Also, if I could help anyone understand any of the topics they were struggling with, it would be a great deed for me.

Thank you in advance. Check out my blog here. For now, I will be posting everyday and slow down when the blog is fairly done :)

I have noticed that there are a lot of problems whose editorials are unwritten on codechef, some editorials of medium hard problems are not understandable for beginners, many useful blog posts on codeforces are unorganized and scattered throughout. So, will it be a good idea if I start a personal wordpress blog? Also, this seems to be a good way to improve myself and have a good measure of how I improve. Thank you in advance :)

Hello CodeForces Community,

I would like to have some help with my solution for Problem D, Santa Claus and a Palindrome. I am missing test case 14 just by a small amount, what is it that I am doing wrong or something that I missed?

Thank you in advance. :D