### Ashishgup's blog

By Ashishgup, 4 weeks ago,

We invite you to participate in CodeChef’s March Cook-Off on 21st March from 9:30 PM — 12:00 AM IST.

There will be 7 problems in Division 3 and 6 problems in Division 2/1.

The March Cook-Off is going to have Gameskraft, Quadeye Securities, Dialpad, and BetterPlace as the official contest recruiters! Gameskraft is hiring for Javascript and Frontend Developers. Quadeye is on the lookout for brilliant Full Stack Developers in CodeChef’s community. Dialpad is looking to attract top talent from CodeChef for the role of Software Engineer. BetterPlace is looking to hire competent coders from the community for SDE 1 and SDE 2 roles.

Joining us on the problem setting panel are:

Problem Submission: If you have original problem ideas, and you’re interested in them being used in CodeChef's contests, you can share them here.

Prizes: Since it is CodeChef's birthday month, the number of prizes being given out are double. That is, the top 20 Indian and top 20 Global participants will receive CodeChef laddus, with which the winners can claim cool CodeChef goodies. Know more here.

There are also special prizes for women:

• Div 1: top 10 females (300 laddus)
• Div 2: top 6 females (150 laddus)
• Div 3: top 6 females (150 laddus)

The video editorials of the problems will be available on our YouTube Channel as soon as the contest ends. Subscribe to get notifications about our new editorials.

Admin Note: Special thanks to Um_nik for helping with shortlisting of problems and providing alternative approaches to the problems!

You can also view your last year's performance report of CodeChef on https://www.codechef.com/report/2021.

• +164

By Ashishgup, history, 7 weeks ago,

We invite you to participate in CodeChef’s CodeChef’s February Lunchtime on 27th February from 7:30 PM — 10:30 PM IST.

There will be 7 problems in Division 3 and 6 problems in Division 2/1.

CodeChef is happy to announce Codenation Innovation Labs (CNIL) as a recruiter for February Lunchtime 2021. CNIL is hiring programmers for the Software Development Engineer role and its Junior Trilogy University (Intern Programme). Programmers from India and across the globe are invited by Codenation Innovation Labs to apply for opportunities at its organization.

Joining us on the problem setting panel are:

Problem Submission: If you have original problem ideas, and you’re interested in them being used in CodeChef's contests, you can share them here.

Prizes: Top 10 Indian and top 10 Global school students from ranklist will receive certificates and CodeChef laddus, with which they can claim cool CodeChef goodies. Know more here.

The video editorials of the problems will be available on our YouTube Channel as soon as the contest ends. Subscribe to get notifications about our new editorials.

Admin Note: Special thanks to Um_nik for his help and for suggesting better solutions for the harder problems.

Good luck and have fun!

• +111

By Ashishgup, 2 months ago,

We invite you to participate in CodeChef’s January Lunchtime on 30th January from 9:00 PM to 12:00 AM IST. Note the unusual time.

There will be 3 divisions, each division containing 6 problems!

This Lunchtime, ByteDance is joining CodeChef as the official contest recruiter! The tech giants, who have their presence globally established through a range of content platforms, are looking to hire for multiple positions for their Singapore office, including — Algorithm Engineers, Backend Engineers, Data Engineers, Data Scientist, Machine Learning Engineers, Research Scientists, Frontend Engineers, Quality Assurance Engineer, Research Engineers, Software Engineer, and Site Reliability Engineers.

Joining us on the problem setting panel are:

Problem Submission: If you have original problem ideas, and you’re interested in them being used in CodeChef's contests, you can share them here.

Prizes: The following will receive CodeChef laddus, with which the winners can claim cool CodeChef goodies. Know more here:

• Top 10 Indian and Global Users (Overall)
• Top 10 Indian and Global School Students

The video editorials of the problems will be available on our YouTube Channel as soon as the contest ends. Subscribe to get notifications about our new editorials.

This Lunchtime is a replay of Codeflows, so most problems do not have subtasks. We have added some easier problems for Div3 and Div2 problemsets, and the contest is delayed from its usual time to avoid clash with the final round!

Good luck and have fun!

Update:

Congratulation to the Codeflows onsite winners:

1. Petr (900/900 points — only one to solve all problems)
2. kabuszki (810/900 points)
3. bicsi (800/900 points)

Update 2:

The January Lunchtime is being made unrated due to the various issues that users faced.

With the high traffic that we have been getting recently, we have been facing issues with our infrastructure, and the contest experience has been bad. Keeping this in mind, we are postponing all rated short contests, till a time when we are sure that the contests can be held smoothly, and we've had a smooth testing round. In particular, the Starters contest scheduled for 31st January is being postponed indefinitely, till further announcements. Apologies for the inconvenience.

Note: The February Long Challenge will take place as usual.

• -39

By Ashishgup, 3 months ago,

We invite you to participate in CodeChef’s January Cook-Off, this Sunday, 24th January, from 9:30 PM to 12:00 AM IST.

There will be 3 divisions, each division containing 6 problems!

This CookOff, ByteDance is joining CodeChef as the official contest recruiter! The tech giants, who have their presence globally established through a range of content platforms, are looking to hire for multiple positions for their Singapore office, including — Algorithm Engineers, Backend Engineers, Data Engineers, Data Scientist, Machine Learning Engineers, Research Scientists, Frontend Engineers, Quality Assurance Engineer, Research Engineers, Software Engineer, and Site Reliability Engineers.

Joining us on the problem setting panel are:

Problem Submission: If you have original problem ideas, and you’re interested in them being used in CodeChef's contests, you can share them here.

Prizes: The top 10 Indian and top 10 Global participants will receive CodeChef laddus, with which the winners can claim cool CodeChef goodies. Know more here.

The video editorials of the problems will be available on our YouTube Channel as soon as the contest ends. Subscribe to get notifications about our new editorials.

Good luck and have fun!

Edit: Sorry for the server issues — it is mostly resolved now, reloading once or twice should work. The contest is extended by 30 minutes and will remain rated.

• +108

By Ashishgup, history, 3 months ago,

Hi Codeforces,

After a recent comment about me not being able to reply to people — I thought I should answer all the questions I can in one place.

Feel free to ask me any questions you have! As a somewhat experienced Competitive Programmer, Problem Setter, Coordinator and DSA interviewer — I will try to answer all the questions I can.

I would also like to bring to your notice, a new YouTube channel (name subject to change) that I am starting with sirjan13 and antipr000, where we will be covering various CS aspects like Competitive Programming, Projects, System Design, etc.

My idea about my role in it so far is:

• Screencasts of contests I participate in, where I explain solutions as I solve
• Problem Solving: Discussing problems I find educational along with some interesting or commonly asked logical puzzles.
• Problem Setting Playlist — Some guidelines for Problem Setting, a tutorial on how to use Polygon and campus.codechef

Other possible things would be discussing interview questions, teaching some topics (I'm considering teaching Dynamic Programming — since almost all videos teach bottom-up, while I prefer and find top-down approach much more intuitive), lockout streams, etc.

Let me know any suggestions regarding what be most interesting for you to watch! I'm considering also making a video based on this blog — where I discuss all the relevant answers in detail.

• +291

By Ashishgup, 4 months ago,

We invite you to participate in CodeChef’s December Cook-Off, this Monday, 21st December, from 9:30 PM to 12:00 AM IST.
Note the unusual time.

You will be given a total of 9 problems (7 in Div2, 7 in Div1) to solve in a duration of 2.5 hours.

Joining us on the problem setting panel are:

Problem Submission: If you have original problem ideas, and you’re interested in them being used in CodeChef's contests, you can share them here.

Prizes: The top 10 Indian and top 10 Global participants will receive CodeChef laddus, with which the winners can claim cool CodeChef goodies. Know more here.

The video editorials of the problems will be available on our YouTube Channel as soon as the contest ends. Subscribe to get notifications about our new editorials.

Good luck and have fun!

• +173

By Ashishgup, 4 months ago,

Hi Codeforces!

I have become a problem reviewer on CodeChef and an admin. We are in need of high-quality problem proposals.

We were not able to reply to quite a few of the submissions regarding their status (Accepted/Rejected), and some may have even gone unnoticed — because the queue of problems has accumulated over the years.

We are now resetting the problem proposals — and now it is estimated that you should receive initial feedback about your problem within 2 weeks of problem submission! If any of your problem proposals submitted before August 2020 have not been accepted or rejected yet, please re-submit them — we apologize for the inconvenience.

The reviewers and admins on CodeChef are now:

Further details are as follows:

• Compensation: The payment details and required difficulties of problems can be found in detail here. Brief summary:

• Submission Form: The form to fill for submitting ideas for any of the contests: Long/CookOff/LunchTime is here.

After submitting the individual problems through the form, you can send an email listing the problems you want in a single short contest. Send it to contest.admin2@codechef.com for Lunchtimes and to contest.admin3@codechef.com for Cook-Offs.

• +185

By Ashishgup, 5 months ago,

Hi everyone!

I would like to invite you to another one of our rounds, that I set with my friends Jeel_Vaishnav, FastestFinger, Utkarsh.25dec, the_hyp0cr1t3 and ridbit10

We had two approved contests, but decided to merge it into one with more logical thinking ^_^

The round Codeforces Round #685 (Div. 2) that will take place on Nov/21/2020 17:35 (Moscow time). If your rating is less than 2100, this round will be rated for you; otherwise, you can participate out of competition.

I would really like to thank my co-setters and:

You will be given 6 problems with one additional subtask and 2 hours 15 minutes to solve them.

Good luck — let the games begin :D

UPD 1: The revised scoring distribution will be: $500 - 750 - 1250 - 1750 - (1500 + 1000) - 3000$

UPD 2: Editorial — Hope you guys enjoyed the round, we will hopefully be back sometime next year :)

UPD 3: Congratulations to the winners! :D

All Participants:

Official Participants:

• +1117

By Ashishgup, 10 months ago,

Hi everyone!

I would like to invite you to another one of our rounds, that I set with my friends FastestFinger, smartnj, the_hyp0cr1t3 and ridbit10.

The round Codeforces Round #651 (Div. 2) will take place on Jun/20/2020 17:35 (Moscow time). If your rating is less than 2100, this round will be rated for you; otherwise, you can participate out of competition.

I would really like to thank my co-setters and:

Based on past reviews, we have:

• Tried to make A easier and make the difficulty gradient a bit better
• Reduced the number of AdHoc problems and made the problemset more diverse

You will be given 6 problems and 2 hours 15 minutes to solve them.

Good luck! :D

The scoring distribution will be: $500 - 1000 - 1500 - 2000 - 2500 - (2000 + 1250)$

Upd: Quick editorial — Hope you guys found the problems interesting :D

• +1654

By Ashishgup, 10 months ago,

Hi everyone!

I would like to invite you to my fifth Codeforces Round, that I set with my friends FastestFinger, Vivek1998299 and ridbit10.

We are excited to bring another contest within a week :D

With that said, I bring to your attention our new Codeforces Round #648 (Div. 2) that will take place on Jun/07/2020 17:35 (Moscow time). If your rating is less than 2100, this round will be rated for you; otherwise, you can participate out of competition.

I would really like to thank:

You will be given 7 problems and 2 hours 15 minutes to solve them.

Good luck! :D

The scoring distribution will be: $500 - 750 - 1250 - 1500 - 2000 - 2500- 3000$

Upd: Quick Editorial — Hope you guys enjoyed the contest :D

• +2104

By Ashishgup, 11 months ago,

Hi everyone!

I would like to invite you to my fourth Codeforces Round, which I have made with my friends FastestFinger and TheOneYouWant. In terms of problems, it is my favorite among all my rounds.

With that said, I bring to your attention our new Codeforces Round #646 (Div. 2) that will take place on May/31/2020 17:35 (Moscow time). If your rating is less than 2100, this round will be rated for you; otherwise, you can participate out of competition.

I would really like to thank:

You will be given 6 problems and 2 hours to solve them. Scoring distribution will be announced later.

Good luck! :D

UPD: Scoring Distribution: $500-1000-1500-2000-2250-3000$

UPD2: Editorial (with memes, and detailed explanation) — Hope you guys enjoyed the contest! :D

• +2050

By Ashishgup, history, 2 years ago,

I hope you guys enjoyed the contest and we hope to host another one soon! The next one will be more balanced :P

With that said, here are the tutorials:

Author: Ashishgup

C++ Code: 51651509

Java Code: 51651164

Author: Ashishgup

C++ Code: 51651887

Java Code: 51651375

Author: Ashishgup

C++ Code: 51652029

Java Code: 51651756

Author: Vivek1998299

C++ Code (Above Logic): 51652491

C++ Code (Mobius Inversion): 51652104

Author: Jeel_Vaishnav

Java Code: 51652167

Author: Jeel_Vaishnav

Java Code: 51652020

• +128

By Ashishgup, history, 2 years ago,

Hello everyone!

I would like to invite you to participate in HackerEarth's February Easy '19. The contest will be held on 1st February, 2019 at 21:00 IST

The problems have been prepared by me (Ashishgup) and Jeel_Vaishnav. We would like to thank TooDumbToWin for testing the round and trytolearn for giving us the opportunity to hold the contest.

You will be given 6 algorithmic questions to solve in 3 hours. Partial scoring will be used (you get points for passing each test case). Although the contest is targeted towards beginners, we hope that everyone finds the tasks interesting. The contest is rated for all and prizes will be awarded to the top 3 beginners (i.e. programmers with a rating of 1600 or less before the challenge starts):

• First place: $75 Amazon gift card. • Second place:$50 Amazon gift card.
• Third place: \$25 Amazon gift card.

Good luck and have fun!

UPD: The contest begins in 15 minutes.

• +66

By Ashishgup, history, 2 years ago,

Creating this blog for discussion of problems/solutions from Indian ICPC Regionals

Onsite Contest Standings:

Online Replay Contests:

There is also the whole issue with test cases in the regionals so far:

Gwalior-Pune:

• "Flipping Polygons" had wrong TCs which affected a few teams, with 3 of them getting AC later. Converting WA -> AC after contest is alright, but the time wasted by teams in trying to correct their codes could have been utilized in solving a different question.
• "Three Strings" had really weak TCs, considering that solutions taking max prefix and max suffix only get AC as well. (Breaking test case: 1 abc cde bcde)

Kolkata-Kanpur:

• "Chef and Alien Invasion" again had wrong TCs, and teams were affected, with even the teams qualifying for World Finals changing places. ACs were converted to WAs after the contest (although that doesn't affect the ranks), not to mention that it was announced that the problemset for the regional was made 1 day before the contest, which is not what is expected of an ICPC regional.

• +258

By Ashishgup, history, 2 years ago,

Hi everyone!

I would like to invite you to my second Codeforces Round, which I have made with my friend and Snackdown partner Jeel_Vaishnav.

With that said, I bring to your attention our new Codeforces Round #523 (Div. 2) that will take place on Nov/22/2018 18:45 (Moscow time). If your rating is less than 2100, this round will be rated for you; otherwise, you can participate out of competition.

I would really like to thank Jeel_Vaishnav for his help with preparing problems, cdkrot for coordinating our round and Um_nik, vintage_Vlad_Makeev, Aleks5d, KeyurJain & Mahir83 for testing the problems. I would also like to thank MikeMirzayanov for Codeforces and Polygon platforms.

You will be given 6 problems and 2 hours to solve them. Scoring distribution will be announced later.

Link to My Coding Library for those interested :)

Good luck! :D

UPD: Scoring Distribution: 500-1000-1500-2000-2500-2750

UPD2: Editorial

• +517

By Ashishgup, 2 years ago,

There are many useful websites that extract data from Codeforces and give some statistics, problem recommendations, graphs, etc.

I thought that collecting them all in one place would be a good idea. Please comment the websites you find useful :D

List as of now:

Some missing sites:

• Most popular users

• +139

By Ashishgup, history, 2 years ago,

Due to my dislike of CodeChef discuss, I choose to discuss/rant about this topic here on Codeforces. Although non-Indian participants may not relate to the ICPC situation, I'm sure the CookOffs and Lunchtimes are a common issue.

First of all, why is the difficulty gradient so fucked up every single time? (Contest Link). Be it ICPC, or CookOffs, or LunchTimes, the same thing is seen over and over again.

Scoreboard for reference:

Secondly, why does online ICPC selection have only 5 questions for 3 hours? Not to mention, 3 of them are pretty hard, and the difficulty drop is huge, so it does not help filter out deserving teams from undeserving ones.

Is ICPC selection supposed to be based on a speed typing test? In unbalanced contests like this, it almost always happens that some undeserving teams qualify. Every penalty matters a lot too. For instance, we failed to qualify for one of the regionals — KGP — because of 1 penalty.

So, my question to CodeChef is: How hard is it to set a balanced contest? Codeforces seems to does it every week. CodeChef fails to do it even in its most important yearly contest, along with its monthly short contests, every single time.

I honestly believe that even I can set a better contest than this. Lastly, why was the leaderboard hidden as soon as the contest ended?

(PS: Teammate's rage after contest: Pic1, Pic2 )

• +718

By Ashishgup, history, 3 years ago,

I have been trying to cover a lot of commonly used Algorithms/Data Structures and maintain neatly written codes at my repository (since most codes are not neatly written in Competitive Programming in general, and I prefer neatly written codes):

https://github.com/Ashishgup1/Competitive-Coding/

Most of the codes are taken from various sources and already existing Coding Libraries, and many Algorithms/Data Structures are missing which I plan to add soon.

Hope you enjoy and feel free to point out any bugs you notice :)

• +120

By Ashishgup, history, 3 years ago,

I hope you guys enjoyed the contest — I hope to host another one soon :D

With that said, here are the tutorials:

Author's Code: 42591712

Author's Code: 42591830

Author's Code: 42591846

Author's Code: 42591882

Author's Code: 42592019

Author's Code: 42592026

Tester(cdkrot)'s Code: 42593206

For O(n3) or O(n2) solution, refer to this comment by pranjal.ssh

• +172

By Ashishgup, history, 3 years ago,

Hi everyone!

It has been almost 2 years since I joined Codeforces, and it has been a great journey as a contestant. I now try to take a shot at problem-setting with my friend Mahir83.

With that said, I bring to your attention my new Codeforces Round #508 (Div. 2) that will take place on Sep/06/2018 18:35 (Moscow time). If your rating is less than 2100, this round will be rated for you; otherwise, you can participate out of competition.

I would like to thank Mahir83 for his help with preparing problems, cdkrot & 300iq for coordinating my round and Um_nik, kraborak, vintage_Vlad_Makeev, vovuh & BledDest for testing my problems. I would also like to thank MikeMirzayanov for Codeforces and Polygon platforms.

You will be given 6 problems and 2 hours to solve them. Scoring distribution will be announced later.

Good luck!

UPD: Scoring Distribution: 500-1000-1500-1750-2250-2750

UPD2: Editorial

• +784

By Ashishgup, history, 3 years ago,

Official announcement here

As per the announcement, the online rounds will start in October 2018 and the onsite finals will be held in February 2019.

• +86

By Ashishgup, history, 3 years ago,

These days, cases of cheating (reported or otherwise) go un-handled as can be seen from this blog. However, this is a cheating case that needs to be handled separately, so it is still somewhat understandable

1) This case where the code is literally copy-pasted letter to letter with the difference being 2 spaces in the entire code?

2) These two submissions from yesterday's contest: 40441960 and 40428475 where there is not even a single character difference. Their codes for C are copied too, albeit with some modification of spaces.

In both of those cases, no-one was disqualified and I'm sure there must be more such cases.

Can we have some way of reporting these cheating cases that are then handled (rather than commenting on blogs or creating new blogs) and a better plagiarism checker?

• +127

By Ashishgup, history, 3 years ago,

Trying to open the Announcement Blogs or Tutorials of some of the past contests (such as: http://codeforces.com/contest/877) gives "Access Denied". What is the reason behind this? Is it a bug?

Screenshot

• +56

By Ashishgup, history, 3 years ago,

In the "Contests" tab, the change along the border of 2100 is shown as "became Candidate Master" both ways. I guess this should either be updated with the current rating system or be removed altogether (if the system only wants to reflect rating system changes from when it was introduced), because right now it is just weird.

• +74

By Ashishgup, history, 3 years ago,

CodeForces seems to have finally introduced a button for copying the sample input on the problem pages :D