Changes in CodeChef Problemsetting Hello Codeforces! For the last half a year I have been working on CodeChef and was proposing ideas on how to change the problemsetting practices (hopefully, for the best). For some time the changes were in brainstorming phase, but as of now many of them are implemented. Today we are ready to share the information with you. But first I would like to approach people who are going to close this blog without reading: If you are not interested in CodeChef contests at all, I think you should change your mind. Monthly short contests (Cook-Off and Lunchtime) have interesting quality problems, on par with Codeforces in my opinion (not AtCoder level yet, but who are?). Long and Starters are more targeted to newbie participants, with more classical educational problems. If you are interested in setting problems for regular contests, you might want to do it on CodeChef. Some reasons: - You don't have to set the whole round, as we work on per problem basis. - This may be especially...

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Free Classes for Palestinian and Lebanese Coders It has been a year since our brothers and sisters in Palestine have been dying and watching their families die. With the war in Lebanon also unfolding, I wondered what I could do. <br> We, Algoritmi Academy, want to do **the least** we can to support people there. We sincerely apologize for not acting sooner. <center> <img src="/predownloaded/0b/dd/0bddd0d56ad33fb2979a34bab5ece9fb076d4d68.jpg" width="40%"> </center> Starting now, we will hold **free weekly classes** for Palestinian and Lebanese coders. Our priority will be those preparing for IOI and ICPC, but we may accept coders preparing for other goals. To participate, register on our [website](https://algoritmiacademy.com/) and select group classes. Our activities are not limited to one class per week; we’ll also have a monthly contest. If the number of participants grows, we’ll make two divisions to better maintain the level. For those who may struggle with English, mention it in your registration form; we may hol...

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CodeChef — ICPC: How hard is it to set a balanced contest? 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](https://www.codechef.com/ACMIND18)). 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 ...

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Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) Salam, Codeforces! $\color{white}{\text{ «Be attentive about your thought that becomes your behavior» «Be attentive about your behavior that becomes your speech» «Be attentive about your speech because it becomes your habit»«Be attentive about your habit because it becomes your personality»«Be attentive about your personality because it becomes your destiny» Said by: Imam Ali}}$ We're so excited to invite you to take part in our round [contest:1864] which will start on [contest_time:1864]. The round will be **rated and open for everyone**. The problems were prepared and authored by [user:amenotiomoi,2023-08-19], Dhruvil [user:Psychotic_D,2023-08-19] Kakadiya, Han [user:wuhudsm,2023-08-19] Jinlong, Amir Hossein [user:Amir_Parsa,2023-08-19] Farhadi, Matthew [user:Chromate00,2023-08-19] Roh, [user:JohnVictor,2023-08-19], [user:odt,2023-08-19], [user:ugly2333,2023-08-19], [user:lavine,2023-08-19], [user:RiverHamster,2023-08-19], [user:flowerletter,2023-08-19] and [user:Aquamoon...

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ZOJ Monthly, January 2019 is coming soon! [ZOJ Monthly, January 2019](http://acm.zju.edu.cn/onlinejudge/contestInfo.do?contestId=382) will be held on Saturday [(time)](https://www.timeanddate.com/worldclock/fixedtime.html?month=1&day=19&year=2019&hour=12&min=00&sec=00&p1=33). The main problem setters are [user:chenjb,2019-01-14] and [user:Claris,2019-01-14]. [Contest Link](http://acm.zju.edu.cn/onlinejudge/contestInfo.do?contestId=382) It will last for 5 hours and have 8-9 problems in total. Since there is no rating system(Thanks to [user:MudCoal,2019-01-14], we may have one in the future) in our [Zhejiang University Online Judge](http://acm.zju.edu.cn/onlinejudge/), it will be unrated. And I guess the difficulty is as a normal Educational Contest in Codeforces. All problem ideas come from members of Zhejiang University Programming Contest Setting Team and most of them have already been used in the Internal Member-Selection Contests in ZJU held in July, 2018. They have been carefully selected, modified, tested by o...

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Bring Back Weekend Contests + Fixed Contest Schedule Hello Codeforces! I think many of us have felt this: you’re excited for a contest, but the timing ends up clashing with school, work, or just life. Some contests appear randomly, and it becomes hard to plan ahead. That’s why I believe we need two things back on Codeforces: Weekend contests – A lot of people (especially students and full-time workers) are only free on weekends Back when we had more contests on Saturdays/Sundays, participation was higher and the atmosphere felt much more “global” Many regions have weekdays packed with exams, jobs, or classes, so weekends are the sweet spot A predictable schedule – Imagine if contests followed a fixed plan, for example: - Sundays = Educational Rounds - Fridays = Div. 2 rounds - Once a month on Saturday = Div. 1+2 combined (Just an example) There might be some contests outside the main schedule, But we can have a global schedule too! Of course the exact schedule can be debated, but the idea is simple: consi...

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On continued fractions. Part 3: In competitive programming Hi everyone! It's been quite some time since I wrote two previous articles in the cycle: [Part 1: Introduction](https://codeforces.me/blog/entry/73655)<br> [Part 2: Properties and interpretation](https://codeforces.me/blog/entry/73687)<br> **Part 3: In competitive programming** This time I finally decided to publish something on how one can actually use continued fractions in competitive programming problems. Few months ago, I joined [CP-Algorithms](https://cp-algorithms.com/algebra/continued-fractions.html) as a collaborator. The website also underwent a major design update recently, so I decided it would be great to use this opportunity and publish my new article there, so here it is: <center><big><b><a href = "https://cp-algorithms.com/algebra/continued-fractions.html">CP-Algorithms &mdash; Continued fractions</a></b></big></center> It took me quite a while to write and I made sure to not only describe common competitive programming challenges related to contin...

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Invitation to TOKI Open Contest February 2017 Hi Codeforces Community, I would like to invite you to participate in TOKI Open Contest. TOKI Open Contest is our (Indonesian's) monthly/bi-monthly online contest. Starting this month, we have decided to make this contest international :) Every problem is written in both Bahasa Indonesia and English. TOKI Open Contest February 2017 will be held on [Saturday, 18 February 2017, 19.00 &mdash; 21.00 Western Indonesian Time (UTC+7)](https://www.timeanddate.com/worldclock/fixedtime.html?msg=TOKI+Open+Contest+February+2017&iso=20170218T12&p1=%3A&ah=2). This contest is written by [user:athin,2017-02-08], [user:anthonyhkf,2017-02-08], [user:aguss787,2017-02-08], and [user:jonathanirvings,2017-02-08]. Several details related to the contest: 1. The contest will use ACM-ICPC scoring type. 2. There will be FIVE problems with various difficulties but the weight for each problem is the same. The contest time is 2 hours. 3. Any non-Accepted submission will get 8 minutes penalty (but ...

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On organizing new Competitive Programming Competitions with awards Hello everybody! As you already know, some high profile competitions, such as GCJ and TCO have been officially discontinued and there is clearly a lack of competitive programming contests with awards for the very best performers. Given the size of the community we have here on Codeforces and on other places too, I think we can use our expertise and our networking to create a new series of competitions (and possibly in the future an organization to help competitive programming grow worldwide) to make up and even pass the existent competitions in prestige and awards. After all, the platform which will be used won't even matter that much, as I see it as a team effort to bring competitive programming to a higher standard in terms of prizes in competition. For example, [Codeforces got $125k](http://codeforces.me/10years/supporters) when people donated for the 10 year badge, which is a lot of money used for expenses such as keeping the servers up, paying problem setters and paying...

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Editorial: VI UnBalloon Contest Hey everyone! I hope everyone enjoyed the problems of [contest:105900]. This editorial contains the description of the solutions and their implementation. Feel free to discuss them in the comments! #### Problem A - Idea: [user:lucassala,2025-05-18] - Preparation: [user:lucassala,2025-05-18] <spoiler summary="Solution"> The problem is designed to deceive and seem like a graph problem, but the constraint that a mountain of a lower level must always be chosen before a mountain of a higher level makes the solution much easier. With this, we can see that it is always possible to pick the mountain of level $1$ before level $2$, and so on. Formally speaking, it is always possible to pick a mountain $i$ before a mountain $j$ if $i < j$. Therefore, the smallest lexicographical order is the numbers from $1$ to $N$, sorted. It is always possible to have an answer, so the possibility of printing $-1$ was also included to distract the competitors. </spoiler> <spoiler summary="C...

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Invitation to TOKI Open Contest March 2018 Hello Codeforces Community, TOKI Open Contest is back again! :D We would like to invite you to participate in this TOKI Open Contest March 2018. TOKI Open Contest is Indonesian (bi-)monthly online programming contest. You may see the January 2018 contest [here](http://codeforces.me/blog/entry/57280)! :) Every problem is written in both Bahasa Indonesia and English. The contest will be divided into **two divisions**: Division 1 and Division 2. It is pretty similar to the divisions in [Atcoder](http://atcoder.jp/) (Beginner and Regular). You are free to register in any division (it's extremely OK if you are a Div2 Codeforces user and register to our Division 1 contest)! The expected difficulties of the problems are much the same with Atcoder's contest problems. TOKI Open Contest March 2018 will be held on [Saturday, 24 March 2018, 19.00 — 21.00 Western Indonesian Time (UTC+7)](https://www.timeanddate.com/worldclock/fixedtime.html?msg=TOKI+Open+Contest+March+2018&iso=20180324T19...

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Invitation to TOKI Open Contest January 2018 Hello Codeforces Community, TOKI Open Contest is back again! :D We would like to invite you to participate in this TOKI Open Contest January 2018. TOKI Open Contest is Indonesian monthly online programming contest. It's been a long hiatus since we decided to make this contest international: on [February](http://codeforces.me/blog/entry/50318) and [March](http://codeforces.me/blog/entry/51134) 2017! :') Every problem is written in both Bahasa Indonesia and English. The contest will be divided into **two divisions**: Division 1 and Division 2. It is pretty similar to the divisions in [Atcoder](http://atcoder.jp/) (Beginner and Regular). You are free to register in any division (it's extremely OK if you are a Div2 Codeforces user and register to our Division 1 contest)! The expected difficulties of the problems are much the same with Atcoder's contest problems. TOKI Open Contest January 2018 will be held on [Saturday, 27 January 2018, 19.00 — 21.00 Western Indonesian Time (UTC+...

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Call for Contest Admin / Problemsetter! We are looking for **contest admins** and **problem setters** for a contest series we are starting at TheJobOverflow. We are experimenting with the format and variety of problems &mdash; the contests are primarily geared toward algorithms/ideas with a lesser component of peeling multilayer observations. TJO has 6,000 users and has evaluated 10,000 solution to programming tasks this week. What is TJO? TheJobOverflow is an **Open Community Platform** for interview preparation & CP. It's built and managed by alumni of IIIT Hyderabad, IIT Bombay, IIT BHU, and IIT Guwahati. Team has ICPC world finalists, IOI medalists, Math olympiad folks and also houses key people who authored math-contest [Gordian Knot](https://codeforces.me/blog/entry/57311) a few years ago ( : Our contest series is yet to be launched, meanwhile we have compiled & tested [**350 problem's Question Bank**](https://thejoboverflow.com/problems/) which includes **latest Coding Round & Interview** problems asked by **Go...

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Invitation to TOKI Open Contest March 2017 Hello Codeforces Community, TOKI Open Contest is back! :D We would like to invite you to participate in this TOKI Open Contest March 2017. TOKI Open Contest is our (Indonesian's) monthly/bi-monthly online contest. Starting last month, we had decided to make this contest international! You may see the information of last month contest [here](http://codeforces.me/blog/entry/50318). Every problem is written in both Bahasa Indonesia and English. Starting this month, we divide the contest into **two divisions**: Division 1 and Division 2. It is pretty similar to the divisions in Codeforces. You are free to register in any division (it's extremely OK if you are a Div2 Codeforces user and register to our Division 1 contest)! The expected difficulties of the problems are much the same with the first four Codeforces' contest problems (A to D). TOKI Open Contest March 2017 will be held on [Saturday, 25 March 2017, 19.00 — 21.00 Western Indonesian Time (UTC+7)](https://www.timeanddate.c...

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Newton's Coding Challenge January 2022 Invite Warm greetings, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **28th January 2022 at 9 PM IST**. Also, do register for [Newton's Grand Coding Contest 2022](https://www.newtonschool.co/grandcodingcontest) and stand a chance to win prizes upto ₹1,000,000. <p> Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. The contest will be <b>rated</b> for all! <p>The problems were written and tested by [user:_Enigma__,2022-01-28], [user:ShlokG,2022-01-28], and [user:iLLusio,2022-01-28]. <p> We would also like to thank [user:gkapatia,2022-01-28] for co-ordinating the contest. <p> Highlights of contest: <ol> <li>The Prize Money for the top 5 performers are as follows: <ul> <li> First Prize: **₹10,000** <li> Second Prize: **₹5,000...

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Invitation to CodeChef December Lunchtime 2019 Greetings Codeforces Community! We invite you to experience the monthly CodeChef Lunchtime for December. The 3-hour contest will offer 5 challenging problems to solve. It will be a great way to close this year on a happy note with your increased ratings! The problem statements of the contest will be available in English, Hindi, Bengali, Russian, Mandarin, and Vietnamese. Also, if you have some original and engaging problem ideas, and you’re interested in them being used in the CodeChef's contests, you can share them here: www.codechef.com/problemsetting/new-ideas. I hope you will participate with your fellow programmers and enjoy the contest problems. Joining me on the problem setting panel are: Setters: Nguyen Ngoc Trung ([user:chemthan,2019-12-28]), Rami Alssadaqa ([user:i_love_islam,2019-12-28]), Hasan Jaddouh ([user:kingofnumbers,2019-12-28]) Tester: Roman Bilyi ([user:RomaWhite,2019-12-28]) Statement Verifier: Jakub Safin ([user:Xellos,2019-12-28]) Mandarin Tran...

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[Codechef] July Long contest 2014 is started!!! <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <b><p> From now on, we will be having the problem statements available in Mandarin Chinese and Russian as well </p></b> <p> As always, the long contests will start on first Friday of every month and last for 10 days. This ensures that two weekends are covered.</p> <p>Continuing from there, we bring you the CodeChef July Challenge 2014 . The July 2014 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/JULY14">http://www.codechef.com/JULY14</a>.<br /><br /> Here are the details:<br /> Date: 4th July 2014 to 14th July 2014<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <b>Problem Setters</b>: - Dmytro Berezin (<a href="http://codeforces.me/profile/Berezin">Berezin</a>), - Gerald Agapov (<a href="http://www.codechef.com/users/gerald">gerald</a>) - Lalit Kundu (<a href="...

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KDOI Rounds List **Latest Update (Nov/26): Round 11 has ended!** Hello, Codeforces! We are the KDOI Team. So far, we have authored so many CP contests, and we would like to make a list of them, to share these contests with you. Hopefully, we will bring more interesting problems and high-quality contests to the whole community! [「KDOI」Round 1](https://www.luogu.com.cn/contest/71146) on Luogu [「KDOI」Round 2](https://www.luogu.com.cn/contest/79091) on Luogu [「KDOI」Round 3](https://www.luogu.com.cn/contest/91607) on Luogu [「KDOI」Round 4, [LGR-130] Luogu Monthly Contest](https://www.luogu.com.cn/contest/98078) on Luogu [「KDOI」Round 5, [MX-X1] MX Weekly Contest · Future 1](https://oier.team/contest/6683e51696c8d7f5bd112568) on MXOJ [「KDOI」Round 6 (Junior Division), [LGR-163] Luogu CSP-J 2023 Simulation](https://www.luogu.com.cn/contest/125612) on Luogu [「KDOI」Round 6 (Senior Division), [LGR-164] Luogu CSP-S 2023 Simulation](https://www.luogu.com.cn/contest/136700) on Luogu [「KDO...

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GoForGold Camp 2024 Wrap Hi everyone! <center> <img height="100px" src="/predownloaded/67/2f/672f239a4b390e85db2408790f5907770547fdb2.jpeg"> <img height="100px" src="/predownloaded/6b/b4/6bb4c1baf053e08ac2257bee4fe8c479b133272b.png"> </center> We're thrilled to share the outcomes of our GoForGold Winter Camp 2024, which marked a significant milestone in strengthening India's competitive programming ecosystem. This December event brought together talented programmers from across the country as part of our ongoing mission to elevate Indian CP to world-class levels. Participation Statistics This edition had an impressive turnout with: 9 teams qualifying for Asia West Continent Finals (out of 33 total qualifiers) 70 participants in our college-focused GoForGold Camp Top Performers ============== We would like to congratulate the top teams and participants across both our divisions. ICPC Camp Division 1 1. 404_solution_not_found: [user:P.V.Sekhar,2025-04-17], [user:sai-17,2025-04-17], [us...

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Invitation to CodeChef June Lunchtime 2019 sponsored by ShareChat! Greetings Codeforces community! CodeChef brings you its last contest of the month, Lunchtime. And everyone's invited! The June Lunchtime 2019, sponsored by ShareChat, is a 3-hour contest and will present you with 5 problems to test your coding abilities. ShareChat — India’s fastest growing social network — is hiring for full-time and internship roles, and participants of the June Lunchtime will have a chance to apply for these exciting opportunities. Visit the contest page for more details. We are on the hunt for a Mandarin Translator to help translate problem statements for our monthly contests. This will be a long-term commitment with translations required thrice a month. If you think you are up to the task, then do get back to us at [email protected]. Additionally, if you have some original and interesting problem ideas, and want them to be used in CodeChef's contests, you can share them here: www.codechef.com/problemsetting/new-ideas I hope you will join your fe...

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Newton's Coding Challenge May 2021 Invite <b>Update: Due a clash with CF round, the contest start time has been moved to 10pm<b> Warm greetings, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **28th May 2021 at 10 PM IST**. The contest will be based on the storyline of the **Game of Thrones**, so don't miss the fun! <p> Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. <p>The problems are written and prepared by [user:aniket9465,2021-05-28] and [user:swapnil07,2021-05-28]. <p> We would also like to thank: <li> [user:gkapatia,2021-05-28] for co-ordinating the contest. <li> [user:jiraya_,2021-05-28] and [user:ak532,2021-05-28] for the valuable feedback throughout. <p> Highlights of contest: <ol> <li>The Prize Money for the top 5 performers are as follows: ...

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Invitation to CodeChef August Challenge 2014 <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <b><p> From now on, we will be having the problem statements available in Mandarin Chinese and Russian as well </p></b> <p> As always, the long contests will start on first Friday of every month and last for 10 days. This ensures that two weekends are covered.</p> <p>Continuing from there, we bring you the CodeChef August Challenge 2014 . The August 2014 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/AUG14">http://www.codechef.com/AUG14</a>.<br /><br /> Here are the details:<br /> Date: 1st August 2014 to 11th August 2014<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <b>Problem Setters</b>: - Constantin Sokol (<a href="http://codeforces.me/profile/kostya_by ">kostya_by </a>), - Devendra Agarwal (<a href="http://codeforces.me/profile/devuy11243">devuy11243</a...

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Educational Codeforces Round 190 [Rated for Div. 2] <img alt="Neapolis University Pafos" src="/predownloaded/9a/33/9a332fadbb47050ba9405057df022a6e37eaf5c0.png" style="float:right;height: 200px; margin: 10px; max-width:40%;"/> Hello Codeforces! The series of Educational Rounds continues thanks to the support of the [Computer Science and Artificial Intelligence (CSAI)] (https://lp.jetbrains.com/academy/csai-program/) program at [Neapolis University Pafos](https://www.nup.ac.cy/), with scholarships provided by JetBrains. [contest:2230] will start on [contest_time:2230]. This round will be **rated for the participants with rating lower than 2100**. It will be held on extended ICPC rules. The penalty for each incorrect submission until the submission with a full solution is 10 minutes. After the end of the contest, you will have 12 hours to hack any solution you want. You will have access to copy any solution and test it locally. **The problems in this round will partially intersect with Saratov SU internal contest (schedul...

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Invitation to CodeChef September Lunchtime 2018! Hello CodeForces Community! We would like to invite you to our next monthly contest and we’re sure you’ll enjoy &mdash; the September Lunchtime 2018 sponsored by Sharechat! Get ready for a three-hour test of your coding brains and pit yourself against the best. And there’s more! We have exciting full-time job opportunities by ShareChat for professionals across the globe. More details can be found on the September Lunchtime contest page. Joining me this time on the problem setting panel are: - Problem Setter: [user:kingofnumbers,2018-09-28] (Hasan Jaddouh) - Problem Tester: [user:teja349,2018-09-28] (Teja Vardhan Reddy) - Editorialist: [user:taran_1407,2018-09-28] (Taranpreet Singh) - Statement Verifier: [user:Xellos,2018-09-28] (Jakub Safin) - Russian Translator: [user:Fedosik,2018-09-28] (Fedor Korobeinikov) - Mandarin Translator: [user:huzecong,2018-09-28] (Hu Zecong) - Hindi Translator: Srijan Dubey - Bengali Translator: [user:solaimanope,2018-09-28] (...

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Invitation to CodeChef June Cook-Off 2019 sponsored by ShareChat! Greetings Codeforces Community! CodeChef’s June CookOff, sponsored by ShareChat is almost here. Prepare to face the problem set that we have been busy brewing. This is your opportunity to showcase your programming skills amidst the best programmers in the world and better your ratings. As a bonus: ShareChat &mdash; India’s fastest growing social network is seeking both interns and full-time employees to join their dynamic team. To be considered for the roles, all you have to do is fill the form provided and participate in the contest. Visit the contest page for more details. We are on the hunt for a Mandarin Translator to help translate problem statements for our monthly contests. This will be a long-term commitment with translations required thrice a month. If you think you are up to the task, then do get back to us at [email protected]. There’s no time to waste, so start flexing your programming muscle. I hope you will join your fellow programmers and enjoy the conte...

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SmallForces Monthly Contest #2 Editorial Thank you very much for participating in our contest. Please share your reviews in the comments. We will continuously bring these types of contests for you. **Don't forget to upsolve these questions.** Here are our top-5 performers: <spoiler summary="Top-5 Performers"> | **Rank** | **Name** | |----------|----------| | $1$ | [user:Minami-Kotobuki,2023-05-24] | | $2$ | [user:HitmanX97,2023-05-24] | | $3$ | [user:realLifeChatGPT,2023-05-24] | | $4$ | [user:Dontony,2023-05-24] | | $5$ | [user:_Mahmoud_Ayman,2023-05-24] | </spoiler> We would also like to mention first solver of every problem: <spoiler summary="First Solver"> | **Problem** | **First Solver** | |----------|----------| | A | [user:_Mahmoud_Ayman,2023-05-24] | | B | [user:HitmanX97,2023-05-24] | | C | [user:Numinous,2023-05-24] | | D | [user:HitmanX97,2023-05-2...

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SmallForces Monthly Contest #1 Editorial Thank you very much for participating in our first contest. Please share your reviews in comments. We will continuously bring these type of contests for you. **Don't forget to upsolve these questions.** Here are our top-5 performers: <spoiler summary="Top-5 Performers"> | **Rank** | **Name** | |----------|----------| | $1$ | [user:cjoa,2023-04-30] | | $2$ | [user:_Mahmoud_Ayman,2023-04-30] | | $3$ | [user:202101101,2023-04-30] | | $4$ | [user:sjNxksbzj,2023-04-30] | | $5$ | [user:Frus,2023-04-30] | </spoiler> We would also like to mention first solver of questions: <spoiler summary="First Solver"> | **Problem** | **First Solver** | |----------|----------| | A | [user:Frus,2023-04-30] | | B1 | [user:adelian,2023-04-30] | | B2 | [user:sjNxksbzj,2023-04-30] | | C | [user:Frus,2023-04-30] | | D | [user:_Mah...

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Editorial for SmallForces Monthly Contest #3 Thank you very much for participating in our contest. Please share your reviews in the comments. We will continuously bring these type of contests for you. Here are solutions with explanations: [A. GobLin and Chess](https://codeforces.me/gym/460558/problem/A) <spoiler summary="Editorial"> In the following question, The Rook can attack the king if the Rook and the King are on the same vertical or horizontal line. It is only possible when $a$ and $x$ are the same or $b$ and $y$ are the same. </spoiler> <spoiler summary="Code"> ```c++ #include <bits/stdc++.h> using namespace std; int main () { int testcase; cin >> testcase; while (testcase--){ int a,b,x,y; cin>>a>>b; cin>>x>>y; if(x == a || y == b){ cout<<"YES"<<endl; } else{ cout<<"NO"<<endl; } } } ``` </spoiler> [B. Odd &mdash; Even Sum](https://codeforces.me/gym/460558/problem/B) <spo...

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Invitation to CodeChef August Cook-Off 2019 Greetings Codeforces Community! You are invited to CodeChef’s August Cook-Off. This is a 2.5-hour coding competition featuring 5 problems and it’s open to programmers across the globe. The contest problems will be available in English, Hindi, Bengali, Russian, Mandarin, and Vietnamese. In addition, if you have some original and engaging problem ideas, and you’re interested in them being used in the CodeChef's contests, you can share them [here] (www.codechef.com/problemsetting/new-ideas). Looking forward to seeing your participation in yet another exciting monthly contest! Joining me on the problem setting panel are: - Setters: [user:kingofnumbers,2019-08-17] (Hasan Jaddouh), [user:Erfan.aa,2019-08-17] (Erfan Alimohammadi), [user:I-Love-Islam,2019-08-17] (Rami Alssadaqa), [user:Atreus,2019-08-17] (Abolfazl Soltani), [user:Reza_H,2019-08-17] (Reza Ashtiani) - Admin: [user:kingofnumbers,2019-08-17] (Hasan Jaddouh) - Tester: [user:teja349,2019-08-17] (Teja Vardhan Reddy) - E...

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Invitation to October Clash on HackerEarth Hello, and, again, you are invited to a monthly contest: [HackerEarth October Clash](https://www.hackerearth.com/october-clash-15/). The problemsetter this time is [user:RomaWhite,2015-10-14]; I'm the tester and editorialist. After all, I have to give [user:I_love_Tanya_Romanova,2015-10-14] a chance to compete! :D The contest takes place this weekend ([starting time](https://www.timeanddate.com/worldclock/fixedtime.html?msg=October%20Clash%20%2715&iso=2015-10-17T01:30:00&p1=64)) and runs for 24 hours. There should be 6 algorithmic problems with partial scoring (points are given independently for passing each test file) and 1 challenge problem. I think the problems are easier than last month, when two subtasks of one problem went unsolved by anyone. Good luck! Btw, round 1 of COCI overlaps with this Clash for 3 hours. That, of course, doesn't mean it's not possible to participate in both at the same time &mdash; [from my own](https://www.hackerearth.com/january-clash/hof/) [...

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Invitation to the November 2013 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <p><b>From now on, we will also be having the problem statements available in Mandarin Chinese and Russian as well :) So invite Russian and Mandarin speaking friends to solve these problems. </b></p> <p> As always, the long contests will start on first Friday of every month and last for 10 days. This ensures that two weekends are covered.</p> <p>We bring you the CodeChef November 2013 Long Challenge. The November 2013 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/NOV13">http://www.codechef.com/NOV13</a>.<br /><br /> Here are the details:<br /> Date: 1st November 2013 to 11th November 2013<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <b>Problem Setters</b>: - Bruno Oliveira (<a href="http://codeforces.me/profile/bruno_oliv">bruno_oliv</a>), - Divyanshu Ranjan...

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Invitation to the April 2014 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <b><p> From now on, we will be having the problem statements available in Mandarin Chinese and Russian as well </p></b> <p> As always, the long contests will start on first Friday of every month and last for 10 days. This ensures that two weekends are covered.</p> <p>Continuing from there, we bring you the CodeChef April 2014 Long Challenge. The April 2014 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/APRIL14">http://www.codechef.com/APRIL14</a>.<br /><br /> Here are the details:<br /> Date: 4th April 2014 to 14th April 2014<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <b>Problem Setters</b>: - Anudeep Nekkanti (<a href="http://codeforces.me/profile/anudeep2011">anudeep2011</a>), - Bruno Oliviera (<a href="http://codeforces.me/profile/kuruma">kuruma</a>), - ...

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Invitation to CodeChef February Cook-Off 2020 Greetings Codeforces Community! CodeChef invites you all to join us at CodeChef’s monthly serving of the Cookoff. A 2.5 hours contest with five servings of challenging problems for you and your peers to relish. Crafted out of the very best ideas, our set of curated problems will take your codebuds on a delightful trip. Further, the February Cookoff will be the perfect opportunity to give a boost to your CodeChef ratings and rankings. Meanwhile, you can also share with us some original and engaging problem ideas which can be used in CodeChef's future contests, here: www.codechef.com/problemsetting/new-ideas. I hope you will participate with your fellow programmers and enjoy the contest problems. Joining me on the problem setting panel are: - Setters: [user:teja349,2020-02-15] (Teja Reddy), [user:adarshagr8,2020-02-15] (Adarsh Agrawal), [user:pshishod2645,2020-02-15] ( Prashant Shishodia), [user:codewiz,2020-02-15] (Nitish Gupta), [user:taran_1407,2020-02-15] (Taranpreet Sin...

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Invitation to SmallForces Monthly Contest #3 Hello coders, I am pleased to invite you to the [SmallForces Monthly Contest #3](https://codeforces.me/contestInvitation/ad959963d54a038ece5eb12a214a59df46b15486) which will be held on [contest_time:460558]. Registrations will start 6 hours before the contest. Difficulty of the problems are Div.3. All the problems were authored and prepared by [user:Vasu_,2023-07-26], [user:naisheelpatel,2023-07-26], [user:hara108,2023-07-26], [user:H_a_r_M_i_t,2023-07-26] and [user:shashank03,2023-07-26]. You will have 120 minutes to solve 6 problems. We would like to thank: - [user:Jalppatel1428,2023-07-30], [user:Gman-343,2023-07-26], [user:Maulik_2493,2023-07-26] for testing the round and giving valuable feedback. - **You**, for participating in the round. We suggest reading all of the problems and hope you will find them interesting! **Good luck to all participants.** Link to the [SmallForces](http://codeforces.me/group/R28ntkjari/blog) group. **UPD1**: The registrati...

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Invitation to the December 2013 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <b><p> From now on, we will be having the problem statements available in Mandarin Chinese and Russian as well </p></b> <p> As always, the long contests will start on first Friday of every month and last for 10 days. This ensures that two weekends are covered.</p> <p>Continuing from there, we bring you the CodeChef December 2013 Long Challenge. The December 2013 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/DEC13">http://www.codechef.com/DEC13</a>.<br /><br /> Here are the details:<br /> Date: 6th December 2013 to 16th December 2013<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <b>Problem Setters</b>: - Bruno Oliveira (<a href="http://codeforces.me/profile/bruno_oliv">bruno_oliv</a>), - Iaroslav Tverdokhlib (<a href="http://codeforces.me/profile/KADR">KADR</...

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Educational Codeforces Round 187 [Rated for Div. 2] <img alt="Neapolis University Pafos" src="/predownloaded/9a/33/9a332fadbb47050ba9405057df022a6e37eaf5c0.png" style="float:right;height: 200px; margin: 10px; max-width:40%;"/> Hello Codeforces! The series of Educational Rounds continues thanks to the support of the [Computer Science and Artificial Intelligence (CSAI)] (https://lp.jetbrains.com/academy/csai-program/) program at [Neapolis University Pafos](https://www.nup.ac.cy/), with scholarships provided by JetBrains. [contest:2203] will start on [contest_time:2203]. This round will be **rated for the participants with rating lower than 2100**. It will be held on extended ICPC rules. The penalty for each incorrect submission until the submission with a full solution is 10 minutes. After the end of the contest, you will have 12 hours to hack any solution you want. You will have access to copy any solution and test it locally. You will be given **6-7 problems** and **2 hours** to solve them. The problems were invent...

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Invitation to the March 2014 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <b><p> From now on, we will be having the problem statements available in Mandarin Chinese and Russian as well </p></b> <p> As always, the long contests will start on first Friday of every month and last for 10 days. This ensures that two weekends are covered.</p> <p>Continuing from there, we bring you the CodeChef March 2014 Long Challenge. The March 2014 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/MARCH14">http://www.codechef.com/MARCH14</a>.<br /><br /> Here are the details:<br /> Date: 7th March 2014 to 17th March 2014<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <b>Problem Setters</b>: - Anudeep Nekkanti (<a href="http://codeforces.me/profile/anudeep2011?">anudeep2011?</a>), - Bruno Oliviera (<a href="http://codeforces.me/profile/kuruma">kuruma</a>),...

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Invitation to the May 2014 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <b><p> From now on, we will be having the problem statements available in Mandarin Chinese and Russian as well </p></b> <p> As always, the long contests will start on first Friday of every month and last for 10 days. This ensures that two weekends are covered.</p> <p>Continuing from there, we bring you the CodeChef May Challenge 2014 . The May 2014 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/May14">http://www.codechef.com/MAY14</a>.<br /><br /> Here are the details:<br /> Date: 2nd May 2014 to 12th May 2014<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <b>Problem Setters</b>: - Anudeep Nekkanti (<a href="http://codeforces.me/profile/anudeep2011">anudeep2011</a>), - Bruno Oliviera (<a href="http://codeforces.me/profile/kuruma">kuruma</a>), - Dmytro Berezin...

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DMOPC '22 September Contest Hello, Codeforces! We are excited to announce that the first DMOJ Monthly Open Programming Competition (DMOPC) of the 2022 season has started today! [](https://dmoj.ca/contest/dmopc22c1) The contest takes place on Friday, September 30th, from [midnight EDT](https://www.timeanddate.com/worldclock/fixedtime.html?msg=DMOPC+%2722+September+Contest&iso=2022-09-30T04%3A00%3A00%2B00%3A00), lasting 4 days until [midnight EDT](https://www.timeanddate.com/worldclock/fixedtime.html?msg=DMOPC+%2722+September+Contest&iso=2022-10-04T04%3A00%3A00%2B00%3A00) on Tuesday, October 4th. Within this 4 day window, you will have **3 hours** to complete the contest. For more details on the contest format, please visit the [contest page](https://dmoj.ca/contest/dmopc22c1). The DMOPC consists of **6 problems** with a wide range of difficulties, and you can get partial marks for partial solutions in the form of **subtasks**. If you cannot sol...

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Invitation to the August 2013 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <p> From now onwards, the long contests will start on first Friday on every month and last for 10 days. This ensures that two weekends are covered.</p> <p> Continuing from there, we bring you the CodeChef August 2013 Long Challenge. The August 2013 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/AUG13">http://www.codechef.com/AUG13</a>.<br /><br /> Here are the details:<br /> Date: 2nd August 2013 to 12th August 2013<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <b>Problem Setter</b>: - Bruno Oliveira (<a href="http://codeforces.me/profile/bruno_oliv">bruno_oliv</a>), - Chen Gaoyuan (<a href="http://codeforces.me/profile/cgy4ever‎">cgy4ever‎</a>), - Ivan Zdomsky (<a href="http://codeforces.me/profile/ballon">ballon</a>), - Kaushik Iska (<a href="http://code...

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Invitation to the October 2013 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <b><p> From now on, we will be having the problem statements available in Mandarin Chinese as well </p> </b> <p> As always, the long contests will start on first Friday of every month and last for 10 days. This ensures that two weekends are covered.</p> <p>Continuing from there, we bring you the CodeChef October 2013 Long Challenge. The October 2013 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/OCT13">http://www.codechef.com/OCT13</a>.<br /><br /> Here are the details:<br /> Date: 4th October 2013 to 14th October 2013<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <b>Problem Setters</b>: - Bruno Oliveira (<a href="http://codeforces.me/profile/bruno_oliv">bruno_oliv</a>), - Ivan Zdomsky (<a href="http://codeforces.me/profile/ballon ">ballon‎</a>), - Kaushik I...

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Invitation to the September 2013 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <p> From now onwards, the long contests will start on first Friday on every month and last for 10 days. This ensures that two weekends are covered.</p> <p> Continuing from there, we bring you the CodeChef September 2013 Long Challenge. The September 2013 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/SEPT13">http://www.codechef.com/SEPT13</a>.<br /><br /> Here are the details:<br /> Date: 6th September 2013 to 16th September 2013<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <b>Problem Setters</b>: - Kaushik Iska (<a href="http://codeforces.me/profile/cauchyk‎">cauchyk‎</a>), - Vivek Hamirwasia (<a href="http://codeforces.me/profile/viv001‎">viv001‎</a>), - Roman Furko (<a href="http://codeforces.me/profile/Furko">Furko</a>), - Vitaliy Herasymiv (<a href="ht...

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Invitation to the July 2013 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <p> From now onwards, the long contests will start on first Friday on every month and last for 10 days. This ensures that two weekends are covered.</p> <p> Continuing from there, we bring you the CodeChef July 2013 Long Challenge. The July 2013 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/JULY13">http://www.codechef.com/JULY13</a>.<br /><br /> Here are the details:<br /> Date: 5th July 2013 to 15th July 2013<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <p> <b>Problem Setter</b>: - Kaushik Iska (<a href="http://codeforces.me/profile/cauchyk">cauchyk</a>), - Hiroto Sekido (<a href="http://codeforces.me/profile/laycurse">laycurse</a>), - Ivan Zdomsky (<a href="http://codeforces.me/profile/ballon">ballon</a>), - Jay Pandya (<a href="http://codeforces.me/prof...

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Invitation to SmallForces Monthly Contest #2 Hello coders, I am glad to invite you to the [SmallForces Monthly Contest #2](https://codeforces.me/contestInvitation/6c367e77595728c0bc9d2443be380f40d5946f1a) which will be held on [contest_time:443861]. Registrations will start 6 hours before the contest. Difficulty of the problems are between Div.2 and Div.3. All the problems were authored and prepared by [user:Vasu_,2023-05-20], [user:jalppatel1428,2023-05-20] and [user:naisheelpatel,2023-05-20]. You will have 150 minutes to solve 7 problems. We would like to thank: - [user:Gman-343,2023-05-20], [user:TrupalPatel,2023-05-20], [user:hara108,2023-05-20] and [user:Dabhi_Dipak,2023-05-20] for testing the round and giving valuable feedback. - **You**, for participating in the round. We strongly recommend you to read all the problems once. We have tried our best to create some good problems. So, I hope you'll enjoy the round and find some problems you like :) Link to the [SmallForces](http://codeforces.me/group...

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Invitation to the 4th Anniversary March 2013 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <p> Continuing from there, we bring you the 4th Anniversary March 2013 Long Challenge. The March 2013 Algorithm Challenge is taking place<b> on <a target="_blank" href="http://www.codechef.com/MARCH13">http://www.codechef.com/MARCH13</a>.<br /><br /> Here are the details:<br /> Date: 1st March 2013 to 11th March 2013<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 Interactive challenge problem.</b> </p> <p> <b>Problem Setters</b>: - Vinayak Garg (<a href="http://codeforces.me/profile/vinayakgarg">vinayakgarg</a>), - Kaushik Iska (<a href="http://codeforces.me/profile/cauchyk">cauchyk</a>), - Vitaliy Herasymiv (<a href="http://codeforces.me/profile/witua">witua</a>), - David Stolp (<a href="http://codeforces.me/profile/pieguy">pieguy</a>), - Tuan Anh (<a href="http://codeforces.me/profile/tuananh93">tuananh93</a>), - Roman Ruban...

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Invitation to the February 2014 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <b><p> From now on, we will be having the problem statements available in Mandarin Chinese and Russian as well </p></b> <p> As always, the long contests will start on first Friday of every month and last for 10 days. This ensures that two weekends are covered.</p> <p>Continuing from there, we bring you the CodeChef February 2014 Long Challenge. The February 2014 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/FEB14">http://www.codechef.com/FEB14</a>.<br /><br /> Here are the details:<br /> Date: 6th February 2014 to 16th February 2014<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <b>Problem Setters</b>: - Lalit Kundu (<a href="http://codeforces.me/profile/darkshadows?">darkshadows?</a>), - Ivan Zdomsky (<a href="http://codeforces.me/profile/ballon">ballon</a>)...

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Invitation to the May 2013 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <p> From now onwards, the long contests will start on first Friday on every month and last for 10 days. This ensures that two weekends are covered.</p> <p> Continuing from there, we bring you the CodeChef May 2013 Long Challenge. The May 2013 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/MAY13">http://www.codechef.com/MAY13</a>.<br /><br /> Here are the details:<br /> Date: 3rd May 2013 to 13th May 2013<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <p> <b>Problem Setter</b>: - Tuan Anh (<a href="http://codeforces.me/profile/tuananh93">tuananh93</a>), - Roman Rubanenko (<a href="http://codeforces.me/profile/Rubanenko">Rubanenko</a>), - Vamsi Kavala (<a href="http://codeforces.me/profile/vamsi.kavala">vamsi.kavala</a>), - Kaushik Iska (<a href="http://codefor...

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Call for Problem Ideas for GoForGold Long Challenges Hello, Codeforces Community! We are excited to announce the **[GoForGold](https://goforgold.in/)** Long Challenges—an innovative monthly contest series brought to you by **[Newton School of Technology](https://www.newtonschool.co/newton-school-of-technology-nst/home)**. Starting on the second last Friday of every month, these challenges will run for 10 days, providing a fantastic platform to learn new things and hone your problem-solving skills. As the Contest Coordinator, I invite you to share your creative problem ideas with us. This is a unique opportunity where you don't have to prepare a full-fledged problem—simply submit your idea. If your idea is accepted, you'll be rewarded with a cash prize! Below is the reward structure based on the difficulty and corresponding Codeforces rating: <table width="100%"> <thead> <tr> <th>Difficulty</th> <th>CF Difficulty Rating</th> <th>Idea Reward (USD)</th> </tr> </thead> <tbody> <tr> ...

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Invitation to the February 2013 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <p> We bring you the CodeChef February 2013 Long Challenge. The February 2013 Algorithm Challenge is taking place<b> on <a target="_blank" href="http://www.codechef.com/FEB13">http://www.codechef.com/FEB13</a>.<br /><br /> Here are the details:<br /> Date: 1st February 2013 to 11th February 2013<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficaulty levels + 1 challenge problem.</b> </p> <p> <b>Problem Setters</b>: - Vinayak Garg (<a href="http://codeforces.me/profile/vinayakgarg">vinayakgarg</a>), - Vitaliy Herasymiv (<a href="http://codeforces.me/profile/witua">witua</a>), - Roman Rubanenko (<a href="http://codeforces.me/profile/Rubanenko">Rubanenko</a>), - Imran Sunny (<a href="http://codeforces.me/profile/sunny">sunny</a>), - Kaushik Iska (<a href="http://codeforces.me/profile/cauchyk">cauchyk</a>), - Khadar Basha (<a href="http://codefor...

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Invitation to the June 2013 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <p> From now onwards, the long contests will start on first Friday on every month and last for 10 days. This ensures that two weekends are covered.</p> <p> Continuing from there, we bring you the CodeChef June 2013 Long Challenge. The June 2013 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/JUNE13">http://www.codechef.com/JUNE13</a>.<br /><br /> Here are the details:<br /> Date: 7th June 2013 to 17th June 2013<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <p> <b>Problem Setter</b>: - TianCheng Lou (<a href="http://codeforces.me/profile/ACRush">ACRush</a>), - Vivek Hamirwasia (<a href="http://codeforces.me/profile/viv001">viv001</a>), - Vitaliy Herasymiv (<a href="http://codeforces.me/profile/witua">witua</a>), - Tasnim Imran Sunny (<a href="http://codeforces...

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Invitation to the April 2013 Long Challenge on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <p> From now onwards, the long contests will start on first Friday on every month and last for 10 days. This ensures that two weekends are covered.</p> <p> Continuing from there, we bring you the CodeChef April 2013 Long Challenge. The April 2013 Algorithm Challenge is taking place<b> on <a target="_blank" href="http://www.codechef.com/APRIL13">http://www.codechef.com/APRIL13</a>.<br /><br /> Here are the details:<br /> Date: 5th April 2013 to 15th April 2013<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <p> <b>Problem Setter</b>: - Anton Lunyov (<a href="http://codeforces.me/profile/Anton_Lunyov">Anton_Lunyov</a>), - David Stolp (<a href="http://codeforces.me/profile/pieguy">pieguy</a>), - Roman Rubanenko (<a href="http://codeforces.me/profile/Rubanenko">Rubanenko</a>), - Kaushik Iska (<a href="http:...

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Codechef Removing Problems from Long Contest So when I woke up this morning I saw that Codechef removed 2 of the 7 problems that were in the monthly long contest, [link](https://www.codechef.com/FEB17?order=desc&sortBy=successful_submissions), because they were “found to be available online”. I wanted to make this post to protest this decision, as I feel like this sets a bad precedent, and does not have many benefits in my opinion. My issue lies with the fact that part of reason I compete in long contest is so that when I do indeed solve a problem, I enjoy being able to look at other solutions after the contest is over, and learning from them. Removing problems makes this impossible I believe, and is also simply discouraging. In addition I feel like the Codechef writers should spend 10 minutes Googling around before putting problem in. If they can not find anything in 10 minutes than I would say even if the problem can indeed be found somewhere, say on Chinese blog with code written in assembly, that it is nontrivial enoug...

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Why has HackerEarth not conducted any contests in February 2024 so far? HackerEarth have three monthly contests, which they conduct every month. - Easy Contest (It usually has 5-6 problems and around 3 hours). - DSA Contest (It usually has 3 problems and 1 and half hours). - Circuits (It has around 7-8 problems and lasts for a week). I eagerly look forward to these contests every month. However, there was no Easy or DSA contest in February 2024. I would just like to know if these contests were just being skipped for this month or whether they are being discontinued altogether. I really love these contests and would really not want them to be discontinued. (CodeChef have stopped Long Contests, LunchTime and CookOffs. HackerRank have stopped all their contests &mdash; Week of Code, Code Ad Infinitum, Hour Rank, Hack101, etc. I really would not want HackerEarth to stop their live contests too). I am posting it here because I do not know any other way to reach HackerEarth. Please let us know. **Update on 8th March** &mdash; I have s...

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Invitation to CodeChef July Cook-Off 2018! Hello CodeForces Community! We’re back with a new and exciting set of coding challenges with the July Cook-Off 2018 sponsored by ShareChat. Plus there are some exciting job/internship opportunities by ShareChat for participants. More details on the July Cook-Off contest page here: Looking forward to seeing your participation in yet another exciting monthly contest! Joining me this time on the problem setting panel are: - Problem Setters: [user:kefaa,2018-07-21] (Kirill Gulin), [user:kingofnumbers,2018-07-21] (Hasan Jaddouh) - Problem Tester: [user:isaf27,2018-07-21] (Ivan Safonov) - Editorialist: [user:vijju123,2018-07-21] (Abhishek Pandey) - Statement verifier: [user:xellos,2018-07-21] (Jakub Šafin) - Russian Translator: [user:Fedosik,2018-07-21] (Fedor Korobeinikov) - Mandarin Translator: [user:huzecong,2018-07-21] (Hu Zecong) - Vietnamese Translator: (VNOI Team) ###Contest Details: **Time:** 22nd July 2018 (2130 hrs) to 23rd July 2018 (0000 hrs). (Indian Stan...

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Harbour.Space Scholarship Contest 2021-2022 (Div. 1 + Div. 2) <img alt="Codeforces and Harbour.Space" src="https://codeforces.me/predownloaded/d7/d0/d7d08f55e940d3b13f74ba80b556ce95b5cc1837.png" style="float:right;height: 150px; margin: 10px; max-width:50%;"/> Hey, Codeforces! We have great news for you. Harbour.Space University is excited to announce **a new contest for all interested programmers** who want to start their studies in Barcelona, Spain or Bangkok, Thailand, and join our ICPC team. The contest will be hosted on the Codeforces platform [contest_time:1553]. We have prepared 9 problems of the joined (Div1 + Div2) level. The round will be **rated and open for everyone.** UPD: Scoring distribution: 250-500-750-1250-1750-2500-3000-3750-5250 UPD2: The [editorial](https://codeforces.me/blog/entry/93105) is out! <center style="margin:2.5em;"> <a href="https://codeforces.me/contests/1553" style="text-decoration:none; font-size:16px; background-color:#685dc5; color:white; font-weight:bold; padding:0.5em 1em;">Sign up ...

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CodeRush December 2023 Invite Warm greetings and Merry Christmas everyone, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **27th December 2023 at 9 PM IST**. <p> Registration Link: [CodeRush](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. The contest will be <b>rated</b> for all! <p>The problems are written by [user:spongebobsquareroot,2023-12-27]. <p> We would also like to thank [user:pradumangoyal,2023-12-27] and [user:gkapatia,2023-12-27] for co-ordinating the round. <p> Highlights of contest: <ol> <li>The Prize Money for the top 5 performers are as follows: <ul> <li> First Prize: **₹10,000** <li> Second Prize: **₹5,000** <li> Third Prize: **₹2,500** <li> Fourth Prize: **₹1,500** <li> Fifth Prize: **₹1,000** </ul> <li> **₹100 Amazon gift vouchers** to the top 50 participants. <li...

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Newton's Coding Challenge September 2022 Invite Warm greetings, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **28th September 2022 at 9 PM IST**. <p> Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. The contest will be <b>rated</b> for all! <p>The problems were written and tested by [user:dnshgyl21,2022-09-28], [user:Lubba_Lubba,2022-09-28], [user:Sawarnik,2022-09-28], [user:Xzirium,2022-09-28], and [user:_Enigma__,2022-09-28]. <p> We would also like to thank [user:pradumangoyal,2022-09-28] and [user:gkapatia,2022-09-28] for co-ordinating the contest. <p> Highlights of contest: <ol> <li>The Prize Money for the top 5 performers are as follows: <ul> <li> First Prize: **₹10,000** <li> Second Prize: **₹5,000** <li> Third Prize: **₹2,500** <li> Fourth Prize: **₹...

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TLE '16 December [Contest Announcement] [With Prizes!]  Hello Codeforces! [user:--d,2016-12-22] and I would like to invite everyone to write the Trudeau Logic Evaluation (TLE) 2016 December contest. The TLE is a monthly contest series written by high school students, predominantly from Pierre Elliott Trudeau High School, Canada. The contest serves as preparation for OI-style contests such as the CCO (Canadian Computing Olympiad) and IOI (International Olympiad in Informatics). The contest will be hosted on the [DMOJ](https://dmoj.ca) platform. The contest will consist of 6 problems, and the problem difficulty will range from Div. 2 A to Div. 1 D. Only problems 4, 5, and 6 will have pretests, and partial points (in the form of subtasks) will be awarded! The contest window will be 24 hours long and will last from [12:00 EST, December 23, 201...

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Newton's Coding Challenge December 2021 Invite Warm greetings, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **28th December 2021 at 9 PM IST**. <p> Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. The contest will be <b>rated</b> for all! <p>The problems were written and tested by [user:dnshgyl21,2021-12-28], [user:Lubba_Lubba,2021-12-28], [user:Sawarnik,2021-12-28], and [user:Xzirium,2021-12-28]. <p> We would also like to thank [user:gkapatia,2021-12-28] for co-ordinating the contest. <p> Highlights of contest: <ol> <li>The Prize Money for the top 5 performers are as follows: <ul> <li> First Prize: **₹10,000** <li> Second Prize: **₹5,000** <li> Third Prize: **₹2,500** <li> Fourth Prize: **₹1,500** <li> Fifth Prize: **₹1,000** </ul> <li> **₹100 Amazon gi...

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Newton's Coding Challenge July 2022 Invite Edit: The [editorials](https://codeforces.me/blog/entry/105844) for the contest have been published. Warm greetings, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **29th July 2022 at 9 PM IST**. <p> Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. The contest will be <b>rated</b> for all! <p>The problems were written and tested by [user:dnshgyl21,2022-07-29], [user:Lubba_Lubba,2022-07-29], [user:Sawarnik,2022-07-29], [user:Xzirium,2022-07-29], and [user:_Enigma__,2022-07-29]. <p> We would also like to thank for co-ordinating the contest. <p> Highlights of contest: <ol> <li>The Prize Money for the top 5 performers are as follows: <ul> <li> First Prize: **₹10,000** <li> Second Prize: **₹5,000** <li> Third Pr...

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Newton's Coding Challenge August 2022 Invite Warm greetings, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **31st August 2022 at 9 PM IST**. <p> Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. The contest will be <b>rated</b> for all! <p>The problems were written and tested by [user:dnshgyl21,2022-08-30], [user:Lubba_Lubba,2022-08-30], [user:Sawarnik,2022-08-30], [user:Xzirium,2022-08-30], and [user:_Enigma__,2022-08-30]. <p> We would also like to thank [user:pradumangoyal,2022-08-30] and [user:gkapatia,2022-07-29] for co-ordinating the contest. <p> Highlights of contest: <ol> <li>The Prize Money for the top 5 performers are as follows: <ul> <li> First Prize: **₹10,000** <li> Second Prize: **₹5,000** <li> Third Prize: **₹2,500** <li> Fourth Prize: **₹1,5...

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Newton's Coding Challenge May 2022 Invite Warm greetings, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **27th May 2022 at 9 PM IST**. <p> Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. The contest will be <b>rated</b> for all! <p>The problems were written and tested by [user:dnshgyl21,2022-04-29], [user:Lubba_Lubba,2022-04-29], [user:Sawarnik,2022-04-29], [user:Xzirium,2022-04-29], and [user:_Enigma__,2022-05-26]. <p> We would also like to thank [user:gkapatia,2022-04-29] for co-ordinating the contest. <p> Highlights of contest: <ol> <li>The Prize Money for the top 5 performers are as follows: <ul> <li> First Prize: **₹10,000** <li> Second Prize: **₹5,000** <li> Third Prize: **₹2,500** <li> Fourth Prize: **₹1,500** <li> Fifth Prize: **₹1,000** </ul...

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Invitation to CodeChef March Cook-off 2016! Hello! Today (20.3.), another monthly Cook-off takes place. It should last for 2.5 hours (21:30 to 00:00 IST) &mdash; [starting time](https://www.timeanddate.com/worldclock/fixedtime.html?msg=CodeChef%3A+March+Cook-Off+2016&iso=20160320T2130&p1=44&ah=2&am=30). **Contest link:** [https://www.codechef.com/COOK68](https://www.codechef.com/COOK68) There will be 5 problems of varying difficulties &mdash; I think they aren't that hard (not for lack of trying on my part), there should be a lot more full scores than last month :D. Feel free to discuss the problems / provide feedback in the comments (after the contest ends). In order to participate, you only need to have a CodeChef account. If you don't have one, you can register [here](https://www.codechef.com/signup). **Problem Setter:** me<br></br> **Problem Tester & Russian Translator:** [user:Antoniuk,2016-03-16] (Vasya Antoniuk)<br></br> **Editorialist:** [user:PraveenDhinwa,2016-03-16] (Praveen Dhinwa)<br></br> **Mandar...

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Newton's Coding Challenge October 2022 Invite Edit: The [editorials](https://codeforces.me/blog/entry/108558) have been published. Warm greetings and Happy Diwali everyone, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **27th October 2022 at 9 PM IST**. The contest will be themed around <b>Diwali, the Indian Festival of Lights!</b> <p> Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. The contest will be <b>rated</b> for all! <p>The problems were written and tested by [user:dnshgyl21,2022-10-26], [user:Lubba_Lubba,2022-10-26], [user:Sawarnik,2022-10-26], [user:Xzirium,2022-10-26], and [user:_Enigma__,2022-10-26]. <p> We would also like to thank [user:pradumangoyal,2022-10-26] and [user:gkapatia,2022-10-26] for co-ordinating the contest. <p> Highlights of cont...

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Newton's Coding Challenge June 2022 Invite Warm greetings, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **24th June 2022 at 9 PM IST**. <p> Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. The contest will be <b>rated</b> for all! <p>The problems were written and tested by [user:dnshgyl21,2022-06-24], [user:Lubba_Lubba,2022-06-24], [user:Sawarnik,2022-06-24], [user:Xzirium,2022-06-24], and [user:_Enigma__,2022-06-24]. <p> We would also like to thank [user:gkapatia,2022-06-24] for co-ordinating the contest. <p> Highlights of contest: <ol> <li>The Prize Money for the top 5 performers are as follows: <ul> <li> First Prize: **₹10,000** <li> Second Prize: **₹5,000** <li> Third Prize: **₹2,500** <li> Fourth Prize: **₹1,500** <li> Fifth Prize: **₹1,000** </u...

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Newton's Coding Challenge November 2021 Invite Warm greetings, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **30th November 2021 at 9 PM IST**. Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **7 problems** and **150 minutes** to solve them. The contest will be <b>rated</b> for all! <p>The problems were written and tested by [user:_Enigma__,2021-11-30], [user:ShlokG,2021-11-30], and [user:iLLusio,2021-11-30]. <p> We would also like to thank [user:gkapatia,2021-11-30] for co-ordinating the contest. <p> Highlights of contest: <ol> <li>The Prize Money for the top 5 performers are as follows: <ul> <li> First Prize: **₹10,000** <li> Second Prize: **₹5,000** <li> Third Prize: **₹2,500** <li> Fourth Prize: **₹1,500** <li> Fifth Prize: **₹1,000** </ul> <li> **₹100 Amazon gift vouchers** to the top 50 participants...

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Newton's Coding Challenge April 2022 Invite **Edit**: The prizes have been distributed and the [editorials](https://codeforces.me/blog/entry/102669) have been published. Warm greetings, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **29th April 2022 at 9 PM IST**. <p> Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. The contest will be <b>rated</b> for all! <p>The problems were written and tested by [user:dnshgyl21,2022-04-29], [user:Lubba_Lubba,2022-04-29], [user:Sawarnik,2022-04-29], and [user:Xzirium,2022-04-29]. <p> We would also like to thank [user:gkapatia,2022-04-29] for co-ordinating the contest. <p> Highlights of contest: <ol> <li>The Prize Money for the top 5 performers are as follows: <ul> <li> First Prize: **₹10,000** <li> Second Prize: **...

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Invitation to CodeChef’s January 2013 Algorithm Challenge — The first contest of the new year! <p> Team CodeChef wishes you all a very Happy New Year! </p> <p> We hope you participated and enjoyed the changes made to monthly Long Contests. We had made some changes to the long contest format to make it more exciting. 10 problems for 10 days! It now has everything for everyone, be it a newbie or a veteran You can read more about it in <a target="_blank" href="http://blog.codechef.com/2012/01/30/the-february-long-challenge-has-a-surprise-in-store/">here</a>. </p> <p> Continuing from there, we bring you the CodeChef January 2013 Long Challenge. The January 2013 Algorithm Challenge is taking place<b> on <a target="_blank" href="http://www.codechef.com/JAN13">http://www.codechef.com/JAN13</a>.<br /><br /> Here are the details:<br /> Date: 1st January 2013 to 11th January 2013<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <p> <b>Problem Setters</b>: - Ivan Zdomsky (<a href="http://codeforce...

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Newton's Coding Challenge October 2021 Invite Warm greetings, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **29th October 2021 at 9 PM IST**. Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. The contest will be <b>rated</b> for all! <p>The problems were written and tested by [user:_Enigma__,2021-10-29], [user:ShlokG,2021-10-29], and [user:iLLusio,2021-10-29]. <p> We would also like to thank [user:gkapatia,2021-10-29] for co-ordinating the contest. <p> Highlights of contest: <ol> <li>The Prize Money for the top 5 performers are as follows: <ul> <li> First Prize: **₹10,000** <li> Second Prize: **₹5,000** <li> Third Prize: **₹2,500** <li> Fourth Prize: **₹1,500** <li> Fifth Prize: **₹1,000** </ul> <li> **₹100 Amazon gift vouchers** to the top 50 participants....

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Codeforces Round #890 (Div. 2) #####Hi, Codeforces! [user:Alexdat2000,2023-08-03], [user:Igorfardoc,2023-08-03], and I are pleased to invite you to our [contest:1856], which will be held on [contest_time:1856]. **This round will be rated for participants with a rating lower than 2100.** We would like to thank: - [user:errorgorn,2023-08-03] for coordinating the round. - [user:Yuu,2023-08-03], [user:maomao90,2023-08-03], [user:thenymphsofdelphi,2023-08-03], [user:Dominater069,2023-08-03], [user:Mike4235,2023-08-03], [user:valeriu,2023-08-03], [user:irkstepanov,2023-08-03], [user:zengminghao,2023-08-03], [user:Gheal,2023-08-03], [user:DeMen100ns,2023-08-03], [user:FEDIKUS,2023-08-03], [user:thanhchauns2,2023-08-03], [user:MinaRagy06,2023-08-03], [user:Java,2023-08-03], [user:xudian,2023-08-03], [user:madlogic,2023-08-03], [user:squishybanana04,2023-08-03], [user:stefanbalaz2,2023-08-03], [user:kobebryan9,2023-08-03], [user:Murinh0,2023-08-03], [user:IlyinAD,2023-08-03], [user:Respectively,2023-08-03], [user:p...

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Newton's Coding Challenge March 2021 Invite Warm greetings, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **26th March 2021 at 9 PM IST**. The contest will be based on the storyline of the **Harry Potter** series, so it'll be fun! <p> Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. <p>The problems were written and prepared by [user:aniket9465,2021-03-24], [user:jiraya_,2021-03-24], and [user:swapnil07,2021-03-24]. <p> We would also like to thank: <li> [user:gkapatia,2021-03-24] for co-ordinating the contest. <li> [user:ak532,2021-03-24] for the valuable feedback throughout. <p> Highlights of contest: <ol> <li>The Prize Money for the top 5 performers are as follows: <ul> <li> First Prize: **₹10,000** <li> Second Prize: **₹5,000** <li> Third Prize: **₹2,...

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Invitation to CodeChef’s October 2012 Algorithm Challenge <p> We hope you participated and enjoyed the changes made to monthly Long Contests. We had made some changes to the long contest format to make it more exciting. 10 problems for 10 days! It now has everything for everyone, be it a newbie or a veteran You can read more about it in <a target="_blank" href="http://blog.codechef.com/2012/01/30/the-february-long-challenge-has-a-surprise-in-store/">here</a>. </p> <p> Continuing from there, we bring you the CodeChef October 2012 Long Challenge. The October 2012 Algorithm Challenge is taking place<b> on <a target="_blank" href="http://www.codechef.com/OCT12">http://www.codechef.com/OCT12</a>.<br /><br /> Here are the details:<br /> Date: 1st October 2012 to 11th October 2012<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <p> <b>Problem Setter</b>: - Gaoyuan Chen (<a href="http://codeforces.me/profile/cgy4ever">cgy4ever</a>), - Kaushik Iska (<a href="h...

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Newton's Coding Challenge September 2021 Invite <b>Edit</b>: The problems have been opened for practice, the [editorials](https://codeforces.me/blog/entry/96450) have been published! Warm greetings, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **30th September 2021 at 9 PM IST**. We sincerely apologize for the failed servers in the last round and believe that the same problem won't arise again. <p> Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. The contest will be <b>rated</b> for all! <p>The problems were written and tested by [user:dnshgyl21,2021-09-29], [user:Lubba_Lubba,2021-09-29], [user:Sawarnik,2021-09-29], [user:Xzirium,2021-09-29], and [user:swapnil07,2021-09-29]. <p> We would also like to thank [user:gkapatia,2021-09-29] for co-ordinating the contest. ...

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Invitation to CodeChef’s December 2012 Algorithm Challenge <p> We hope you participated and enjoyed the changes made to monthly Long Contests. We had made some changes to the long contest format to make it more exciting. 10 problems for 10 days! It now has everything for everyone, be it a newbie or a veteran You can read more about it in <a target="_blank" href="http://blog.codechef.com/2012/01/30/the-february-long-challenge-has-a-surprise-in-store/">here</a>. </p> <p> Continuing from there, we bring you the CodeChef December 2012 Long Challenge. The December 2012 Algorithm Challenge is taking place<b> on <a target="_blank" href="http://www.codechef.com/DEC12">http://www.codechef.com/DEC12</a>.<br /><br /> Here are the details:<br /> Date: 1st December 2012 to 11th December 2012<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <p> <b>Problem Setter</b>: - Vamsi Kavala (<a href="http://codeforces.me/profile/vamsi_kavala">vamsi_kavala</a>), - Anton Lunyov...

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Invitation to CodeChef October Lunchtime 2018! Hello Codeforces Community! We would like to invite you to our next monthly contest and we’re sure you’ll enjoy &mdash; the October Lunchtime 2018 sponsored by Sharechat! Along with interesting problem sets, we have exciting full-time job opportunities by ShareChat for professionals across the globe. More details can be found on the October Lunchtime contest page. Joining me this time on the problem setting panel are: - Problem Setter: [user:kingofnumbers,2018-10-26] (Hasan Jaddouh), [user:PraveenDhinwa,2018-10-26] (Praveen Dhinwa) - Problem Tester: [user:teja349,2018-10-26] (Teja Vardhan Reddy) - Editorialist: [user:taran_1407,2018-10-26] (Taranpreet Singh) - Statement Verifier: [user:Xellos,2018-10-26] (Jakub Safin) - Russian Translator: [user:Fedosik,2018-10-26] (Fedor Korobeinikov) - Mandarin Translator: [user:huzecong,2018-10-26] (Hu Zecong) - Hindi Translator: Akash Shrivastav - Bengali Translator: Imran Hasan - Vietnamese Translator: VNOI Team ...

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Newton's Coding Challenge June 2021 Invite Warm greetings, [Newton School](https://www.newtonschool.co/) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/contest/all/). The challenge will go live on **30th June 2021 at 9 PM IST**. The contest will have our dearest characters from **FRIENDS**! <p> Registration Link: [Newton's Coding Challenge](https://my.newtonschool.co/contest/all/) <p> You will be given **6 problems** and **150 minutes** to solve them. <p>The problems are written and prepared by [user:aniket9465,2021-06-30] and [user:swapnil07,2021-06-30]. <p> We would also like to thank: <li> [user:gkapatia,2021-06-30] for co-ordinating the contest. <li> [user:jiraya_,2021-06-30] and [user:ak532,2021-06-30] for the valuable feedback throughout. <p> Highlights of contest: <ol> <li>The Prize Money for the top 5 performers are as follows: <ul> <li> First Prize: **₹10,000** <li> Second Prize: **₹5,000** <li> Third Prize: **₹2,500** <li> Fourth Prize: **₹...

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Invitation to CodeChef’s November 2012 Algorithm Challenge <p> We hope you participated and enjoyed the changes made to monthly Long Contests. We had made some changes to the long contest format to make it more exciting. 10 problems for 10 days! It now has everything for everyone, be it a newbie or a veteran You can read more about it in <a target="_blank" href="http://blog.codechef.com/2012/01/30/the-february-long-challenge-has-a-surprise-in-store/">here</a>. </p> <p> Continuing from there, we bring you the CodeChef November 2012 Long Challenge. The November 2012 Algorithm Challenge is taking place<b> on <a target="_blank" href="http://www.codechef.com/NOV12">http://www.codechef.com/NOV12</a>.<br /><br /> Here are the details:<br /> Date: 1st November 2012 to 11th November 2012<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <p> <b>Problem Setters</b>: - David Stolp (<a href="http://codeforces.me/profile/pieguy">pieguy</a>), - Roman Rubanenko (<a href...

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Invitation to CodeChef’s August 2012 Algorithm Challenge <p> We hope you participated and enjoyed the changes made to monthly Long Contests. We had made some changes to the long contest format to make it more exciting. 10 problems for 10 days! It now has everything for everyone, be it a newbie or a veteran You can read more about it in <a target="_blank" href="http://blog.codechef.com/2012/01/30/the-february-long-challenge-has-a-surprise-in-store/">here</a>. </p> <p> Continuing from there, we bring you the CodeChef August 2012 Long Challenge. The August 2012 Algorithm Challenge is taking place<b> on <a target="_blank" href="http://www.codechef.com/AUG12">http://www.codechef.com/AUG12</a>.<br /><br /> Here are the details:<br /> Date: 1st August 2012 to 11th August 2012<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <p> <b>Problem Setters</b>: - Gennady Korotkevich (<a href="http://codeforces.me/profile/tourist ">tourist </a>), - Kaushik Iska (<a hre...

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Invitation to CodeChef’s July 2012 Algorithm Challenge <p> We hope you participated and enjoyed the changes made to monthly Long Contests. We had made some changes to the long contest format to make it more exciting. 10 problems for 10 days! It now has everything for everyone, be it a newbie or a veteran You can read more about it in <a target="_blank" href="http://blog.codechef.com/2012/01/30/the-february-long-challenge-has-a-surprise-in-store/">here</a>. </p> <p> Continuing from there, we bring you the CodeChef July 2012 Long Challenge. The July 2012 Algorithm Challenge is taking place<b> on <a target="_blank" href="http://www.codechef.com/JULY12">http://www.codechef.com/JULY12</a>.<br /><br /> Here are the details:<br /> Date: 1st July 2012 to 11th July 2012<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <p> <b>Problem Setters</b> : - Namit Shetty (<a href="http://codeforces.me/profile/shettynamit">shettynamit</a>), - Shanjingbo, - Kamran ma...

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hihoCoder Challenge 26 Hello everyone, hihoCoder is going to hold a [contest](http://hihocoder.com/contest/challenge26) at the first day of this year. ([2017/01/01 19:00 UTC+8](https://www.timeanddate.com/worldclock/fixedtime.html?day=1&month=1&year=2017&hour=14&min=0&sec=0&p1=166)) hihoCoder is a Chinese website which holds some contests for beginners and also a monthly challenge. The contest lasts 2 hours and contains 4 problems. The problem set is prepared by me and [user:jiry_2,2016-12-31]. There will be english translation of the problems. The hardest problem is as hard as div1 C/D in my mind. Enjoy problems!

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Invitation to CodeChef’s September 2012 Algorithm Challenge <p> We hope you participated and enjoyed the changes made to monthly Long Contests. We had made some changes to the long contest format to make it more exciting. 10 problems for 10 days! It now has everything for everyone, be it a newbie or a veteran You can read more about it in <a target="_blank" href="http://blog.codechef.com/2012/01/30/the-february-long-challenge-has-a-surprise-in-store/">here</a>. </p> <p> Continuing from there, we bring you the CodeChef September 2012 Long Challenge. The September 2012 Algorithm Challenge is taking place<b> on <a target="_blank" href="http://www.codechef.com/SEP12">http://www.codechef.com/SEP12</a>.<br /><br /> Here are the details:<br /> Date: 1st September 2012 to 11th September 2012<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <p> <b>Problem Setters</b>: - Gennady Korotkevich (<a href="http://codeforces.me/profile/tourist ">tourist </a>), - Kaushik ...

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Invitation to CodeChef’s June 2012 Algorithm Challenge <p> We hope you participated and enjoyed the changes made to monthly Long Contests. We had made some changes to the long contest format to make it more exciting. 10 problems for 10 days! It now has everything for everyone, be it a newbie or a veteran You can read more about it in <a target="_blank" href="http://blog.codechef.com/2012/01/30/the-february-long-challenge-has-a-surprise-in-store/">here</a>. </p> <p> Continuing from there, we bring you the CodeChef June 2012 Long Challenge. The June 2012 Algorithm Challenge is taking place<b> on <a target="_blank" href="http://www.codechef.com/JUNE12">http://www.codechef.com/JUNE12</a>.<br /><br /> Here are the details:<br /> Date: 1st June 2012 to 11th June 2012<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <p> <b>Problem Setter</b>: IstvanNagy (<a href="http://codeforces.me/profile/iscsi">iscsi</a>), Namit Shetty(<a href="http://codeforces.me/pro...

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Invitation to CodeChef’s April 2012 Algorithm Challenge <p> We hope you participated and enjoyed the changes made to monthly Long Contests. We had made some changes to the long contest format to make it more exciting. 10 problems for 10 days! It now has everything for everyone, be it a newbie or a veteran :) You can read more about it in <a href="http://blog.codechef.com/2012/01/30/the-february-long-challenge-has-a-surprise-in-store/">here</a>. </p> <p> Continuing from there, we bring you the CodeChef April 2012 Long Challenge. The April 2012 Algorithm Challenge is taking place<b> on <a href="http://www.codechef.com/APRIL12">http://www.codechef.com/APRIL12</a>.<br /><br /> Here are the details:<br /> Date: 1st April 2012 to 11th April 2012<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <p> <b>Problem Setter</b>: Sergey Kulik, Kaushik Iska (<a href="http://codeforces.me/profile/cauchyk">cauchyk</a>), Tomaž Hočevar (<a href="http://codeforces.me/pro...

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CodeRush January 2024 Invite **Update**: The contest goes live today at 9pm. <p> Warm greetings and Happy New Year everyone! [Newton School](https://my.newtonschool.co/register/newtons-coding-challenge/?utm_source=codeforces_blog&utm_medium=codeforces-user&utm_campaign=codeforces-25-01-2024-blog-post&utm_namespace=coderush&utm_hash=ns_c1cicxcclecv) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/register/newtons-coding-challenge/?utm_source=codeforces_blog&utm_medium=codeforces-user&utm_campaign=codeforces-25-01-2024-blog-post&utm_namespace=coderush&utm_hash=ns_c1cicxcclecv). The challenge will go live on **29th January 2024 at 9 PM IST**. <p> Registration Link: [CodeRush](https://my.newtonschool.co/register/newtons-coding-challenge/?utm_source=codeforces_blog&utm_medium=codeforces-user&utm_campaign=codeforces-25-01-2024-blog-post&utm_namespace=coderush&utm_hash=ns_c1cicxcclecv) <p> You will be given **6 problems** and **150 minutes** to solve them. The ...

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Invitation to the June Challenge 2014 on CodeChef <p> We hope you participated and enjoyed the changes made to monthly Long Contests. </p> <b><p> From now on, we will be having the problem statements available in Mandarin Chinese and Russian as well </p></b> <p> As always, the long contests will start on first Friday of every month and last for 10 days. This ensures that two weekends are covered.</p> <p>Continuing from there, we bring you the CodeChef June Challenge 2014 . The June 2014 Algorithm Challenge is taking place on <b><a target="_blank" href="http://www.codechef.com/JUNE14">http://www.codechef.com/JUNE14</a>.<br /><br /> Here are the details:<br /> Date: 6th June 2014 to 16th June 2014<br /> Duration: 10 days<br /> Problems: 9 binary problems of varying difficulty levels + 1 challenge problem.</b> </p> <b>Problem Setters</b>: - Dmytro Berezin (<a href="http://codeforces.me/profile/Berezin">Berezin</a>), - Gedi Zheng (<a href="http://codeforces.me/profile/stzgd">stzgd</a>), - Istvan Nagy (<a href="ht...

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Participate in HackerEarth's Monthly September Hard Contest Hello everyone, I want to invite all of you the next edition of one of the monthly contests on [HackerEarth](www.hackerearth.com )- this particular challenge for the month of September is called the September Clash. The duration for the same being 12 hours, consisting of 5 problems, of various difficulty levels. 1 Medium, 3 Hard, and 1 Challenge problem to keep you occupied for 12 hours. You can register for the contest at: [September Clash](http://www.hackerearth.com/september-clash/ )- Let's see all of you here to make the contest bigger and solve some really mind boggling problems as one of the perks. Problem Setters: [Akashdeep Nain](http://codeforces.me/profile/akashdeep) ,[Lokesh Khandelwal](http://codeforces.me/profile/phantom11),[Prateek Gupta](http://codeforces.me/profile/Xsquare),[Akash Agrawall](http://hackerearth.com/users/akash.wanted) Editorialist : [Lokesh Khandelwal](http://codeforces.me/profile/phantom11) Date : 20 September,2014 Time : [check tim...

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What happened to Codechef? Codechef used to conduct two programming contests monthly, cook-off and lunch-time but this month neither of them were conducted so basically there was no contest for div 1 users, also seems liks cook-off has been discontinued since July 2022. I find it really disappointing because both these contests had really nice and enjoyable problems. I am not sure of the reason but I do feel that they are more focused on the majority of the people who are in div 2/3/4 on Codechef. I was expecting more contests for div 1 in future but what is happening is completely opposite :( I understand it requires a lot of efforts by different people to make quality problems but they are putting efforts in organising a lot of starter contests which I don't know if is better to sacrifice for the only div 1 contests they used to have. Is there someone from Codechef who knows why this has happened or if there going to be more div 1 contests in future? UPD: It's good to know that CC Starters 62...

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[HackerRank] Ad Infinitum September'14 Math Programming Contest Hi! Ad Infinitum is back with [Infinitum September'14](https://www.hackerrank.com/infinitum-sep14), a monthly contest restricted to mathematics domain, held on HackerRank. Register at https://www.hackerrank.com/infinitum-sep14 The contest commences [on 19^th September 15:30 UTC](http://www.timeanddate.com/worldclock/fixedtime.html?msg=%5BHackerRank%5D+Ad+Infinitum+September%2714&iso=20140919T1530&p1=1440). You are allowed to enter the contest anytime, for tie breaking the timer will start when you view the first challenge, which allows you to start late at your convenience, but once started try to finish as fast as possible to be on top of the leaderboard :) It's a 2 days contest with 8 problems (3 Easy, 3 Medium, 2 Hard) Scoring Distribution: 20 25 30 40 60 80 100 120 **Top 10 on leaderboard gets Cool HackerRank T shirt,** **Contributers** [user:kevinsogo,2014-09-19] [user:OoO000oOOOoOooOo,2014-09-19] [user:sevenkplus,2014-09-19] [u...

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TLE '16 September [Contest announcement]  Hello Codeforces users! [user:ZQFMGB12,2016-09-19], [user:nathanlo99,2016-09-19] and I would like to invite everyone to write the Trudeau Logic Evaluation (TLE) 2016 September contest. The TLE is a monthly contest series written by high school students, predominantly from Pierre Elliott Trudeau High School, Canada. The contest serves as preparation for OI-style contests such as CCO and IOI. The contest will be hosted on the [DMOJ](https://dmoj.ca) platform. The contest will consist of 6 problems, and the problem difficulty will range from Div. 2 A to Div. 1 C. <strike>All problems</strike> Only problems 4, 5, and 6 will have pretests, and partial points (in the form of subtasks) will be awarded! The contest window will be 11 hours long and will last from [12:00 EDT to 23:00 EDT on S...

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[HackerRank] Ad Infinitum 10 — Math Programming Contest Hi! Ad Infinitum is back with [10th Edition](https://www.hackerrank.com/infinitum10), a monthly contest restricted to mathematics domain, held on HackerRank. Register at https://www.hackerrank.com/infinitum10 The contest commences [on 20^th February 15:30 UTC](http://www.timeanddate.com/worldclock/fixedtime.html?msg=%5BHackerRank%5D+Ad+Infinitum+10&iso=20150220T1530&p1=1440). You are allowed to enter the contest anytime, for tie breaking the timer will start when you view the first challenge, which allows you to start late at your convenience, but once started try to finish as fast as possible to be on top of the leaderboard :) It's a 2 days contest with 8 problems (3 Easy(Tutorial), 3 Medium, 2 Hard) Scoring Distribution: 20 20 20 40 60 80 100 120 **Top 10 on leaderboard gets Cool HackerRank T shirt,** **Special prizes and Job Opportunities for Indian participants.** **Contributers** [user:kevinsogo,2015-02-20] [user:bayleef,2015-02-...

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CodeRush March 2024 Invite <b>Update</b>: The contest goes live today, **4th March 2024 at 9 PM IST**. Warm greetings! [Newton School](https://my.newtonschool.co/register/newtons-coding-challenge/?utm_source=codeforces_blog&utm_medium=codeforces-user&utm_campaign=codeforces-27-02-2024-blog-post&utm_namespace=coderush&utm_hash=ns_u5naide7gn47) cordially invites you to be a part of our [monthly coding contest](https://my.newtonschool.co/register/newtons-coding-challenge/?utm_source=codeforces_blog&utm_medium=codeforces-user&utm_campaign=codeforces-27-02-2024-blog-post&utm_namespace=coderush&utm_hash=ns_u5naide7gn47). The challenge will go live on **4th March 2024 at 9 PM IST**. <p> Registration Link: [CodeRush](https://my.newtonschool.co/register/newtons-coding-challenge/?utm_source=codeforces_blog&utm_medium=codeforces-user&utm_campaign=codeforces-27-02-2024-blog-post&utm_namespace=coderush&utm_hash=ns_u5naide7gn47) <p> You will be given **6 problems** and **150 minutes** to solve them. The contest ...

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Useful links <p class="MsoNormal"><span class="apple-style-span"><b style="mso-bidi-font-weight: normal"><span style="font-size:10.0pt;font-family:&quot;Arial&quot;,&quot;sans-serif&quot;; color:red;background:white;mso-ansi-language:EN-US">Hi everyone!</span></b></span><span class="apple-converted-space"><b style="mso-bidi-font-weight:normal"><span style="font-size:10.0pt;font-family:&quot;Arial&quot;,&quot;sans-serif&quot;;color:red;background: white;mso-ansi-language:EN-US">&nbsp;</span></b></span><span class="apple-style-span"><b style="mso-bidi-font-weight:normal"><span style="font-size:10.0pt;font-family:&quot;Arial&quot;,&quot;sans-serif&quot;;color:red;background: white;mso-ansi-language:EN-US">Here are the useful links of olympiad programming.</span></b></span><span class="apple-converted-space"><b style="mso-bidi-font-weight:normal"><span style="font-size:10.0pt;font-family: &quot;Arial&quot;,&quot;sans-serif&quot;;color:red;background:white;mso-ansi-language:EN-US">&nbsp;</span></b...

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A job for the red one Hi guys! I'm currently unemployed, looking for a job and would like to make some survey here, basically the topic would be "the interesting job". To give you a quick introduction: I was working as a .Net developer for around 7 years in different but more or less similar outsourcing companies, I've started participating in competitive programming 1.5 years ago and eventually this ruined my career in regular outsourcing cause the tasks there most of the time are more boring and less brain-teasing than what you have in CP. To be clear, what I want here is to have as much opinions as possible, I would appreciate any ideas, consider this topic to be a brainstorming platform. I just want to broaden my understanding of what is there outside of the companies where I was working before. I'm interested to hear about your companies (I won't blame you if you decide to advertise your company in this blog post), or maybe you won't give out the company name but will share what do you do there,...

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[HackerRank] Ad Infinitum 9 — Math Programming Contest Hi! Ad Infinitum is back with [9th Edition](https://www.hackerrank.com/infinitum9), a monthly contest restricted to mathematics domain, held on HackerRank. Register at https://www.hackerrank.com/infinitum9 The contest commences [on 12^th December 15:30 UTC](http://www.timeanddate.com/worldclock/fixedtime.html?msg=%5BHackerRank%5D+Ad+Infinitum+9&iso=20141212T1530&p1=1440). You are allowed to enter the contest anytime, for tie breaking the timer will start when you view the first challenge, which allows you to start late at your convenience, but once started try to finish as fast as possible to be on top of the leaderboard :) It's a 2 days contest with 8 problems (3 Easy, 3 Medium, 2 Hard) Scoring Distribution: 20 20 20 40 60 80 100 120 **Top 10 on leaderboard gets Cool HackerRank T shirt,** **Contributers** [user:kevinsogo,2014-12-12] [user:Bugman,2014-12-12] [user:bayleef,2014-12-12] [user:amitp08,2014-12-12] [user:minimario,2014-...

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More contests similar to April Fools Day contest Today I saw a [thread](http://codeforces.me/blog/entry/11391#comment-163525) where users were discussing that we can have these type of contests more frequently than once a year. I too share this opinion, and I have an idea for this. Let Codeforces have **two different ratings** (like TopCoder has Algorithm and Marathon ratings separately). - The first (already existing **Algorithm** rating) will be for regular contests. This will be the "actual" rating, and CF already has this. - The second one (we can call it **Fool's Gold** or some funny name :D) will be for contests like the April Fools contest, which can be held probably once in a month! Ideally it could be 1st of every month, but the exact schedule can be decided by admins. I agree that organizing this type of contests monthly will be time-consuming for the setters, so maybe we can have fewer problems (less than the 9 we had in [this month's contest](http://codeforces.me/contest/409)), ideally about 4-5 problems per c...

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TLE '16 October [Contest announcement]  Hello Codeforces users! [user:ZQFMGB12,2016-10-13], [user:nathanlo99,2016-10-13] and I would like to invite everyone to write the Trudeau Logic Evaluation (TLE) 2016 October contest. The TLE is a monthly contest series written by high school students, predominantly from Pierre Elliott Trudeau High School, Canada. The contest serves as preparation for OI-style contests such as CCO (Canadian Computing Olympiad) and IOI (International Olympiad in Informatics). The contest will be hosted on the [DMOJ](https://dmoj.ca) platform. The contest will consist of 6 problems, and the problem difficulty will range from Div. 2 A to Div. 1 C/D :) . Only problems 4, 5, and 6 will have pretests, and partial points (in the form of subtasks) will be awarded! The contest window will be 11 hours long and...

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[HackerRank] Ad Infinitum 8 — Math Programming Contest Hi! Ad Infinitum is back with [8th Edition](https://www.hackerrank.com/infinitum-sep14), a monthly contest restricted to mathematics domain, held on HackerRank. Register at https://www.hackerrank.com/infinitum8 The contest commences [on 17^th October 15:30 UTC](http://www.timeanddate.com/worldclock/fixedtime.html?msg=%5BHackerRank%5D+Ad+Infinitum+8&iso=20141017T1530&p1=1440). You are allowed to enter the contest anytime, for tie breaking the timer will start when you view the first challenge, which allows you to start late at your convenience, but once started try to finish as fast as possible to be on top of the leaderboard :) It's a 2 days contest with 8 problems (3 Easy, 3 Medium, 2 Hard) Scoring Distribution: 20 25 30 40 60 80 100 120 **Top 10 on leaderboard gets Cool HackerRank T shirt,** **Contributers** [user:kevinsogo,2014-10-17] [user:OoO000oOOOoOooOo,2014-10-17] [user:Bugman,2014-10-17] [user:bayleef,2014-10-17] [user:de...

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TLE '16 January [Contest announcement]  Hello Codeforces! [user:ZQFMGB12,2017-01-19] and I would like to invite everyone to write the Trudeau Logic Evaluation (TLE) 2016 January contest. The TLE is a monthly contest series written by high school students, predominantly from Pierre Elliott Trudeau High School, Canada. The contest serves as preparation for OI-style contests such as the CCO (Canadian Computing Olympiad) and IOI (International Olympiad in Informatics). The contest will be hosted on the [DMOJ](https://dmoj.ca) platform. The contest will consist of 6 problems, and the problem difficulty will range from Div. 2 A to Div. 1 D. Only problems 4, 5, and 6 will have pretests, and partial points (in the form of subtasks) will be awarded! The contest window will be 11 hours long and will last from [12:00 EST to 23:00 EST ...

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Educational Codeforces Round 191 [Rated for Div. 2] <img alt="Neapolis University Pafos" src="/predownloaded/9a/33/9a332fadbb47050ba9405057df022a6e37eaf5c0.png" style="float:right;height: 150px; margin: 10px; max-width:40%;"/> Hello Codeforces! The series of Educational Rounds continues thanks to the support of the [Neapolis University Pafos](https://www.nup.ac.cy/bsc-in-computer-science-and-artificial-intelligence). On [contest_time:2233] [contest:2233] will start. This round will be **rated for the participants with rating lower than 2100**. It will be held on extended ICPC rules. The penalty for each incorrect submission until the submission with a full solution is 10 minutes. After the end of the contest, you will have 12 hours to hack any solution you want. You will have access to copy any solution and test it locally. You will be given **6 or 7 or 67 problems** and **2 hours** to solve them. The problems were invented and prepared by Ivan [user:BledDest,2026-04-16] Androsov and me. Also, huge thanks to Mike [...

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Codeforces Future Rating Predictor — Visualize Where You're Headed #### **What this app does** Plots your entire rating history from your very first contest and overlays a fitted regression curve (linear, quadratic, or cubic) to best approximate your rating trend [Projected curve fit into your rating chart](/predownloaded/3a/06/3a06351d1ffbe3526d7a6add7b6026053b4e063a.png) [Actual contest rating changes in all the contests a user has participated in so far](/predownloaded/be/65/be652a3cc4ddfa320c6bdb45b7e503eff87478d5.png) [Hover over the projected curve to see the predicted ratings at each timestamp/date till December 2025](/predownloaded/ed/1c/ed1ca4a08ace5d4756eacc0cf27dc87f880b81c2.png) Predicts your future rating month-by-month until December 2025. [Future Rating Predictions (Monthly till Dec 2025)](/predownloaded/a3/72/a372b1f8268f5d20fe794493242e88161703ddda.png) #### **Approach** **1. Fetches a user's entire contest history** : [Codeforces RatingChange API](https://codeforces.me/apiHelp/objects#RatingChange) Each co...

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Monthly Programming Contest #2 , by Programming Club IIT Kanpur on Codechef Hello everyone, <br><br> I would like to invite you to participate in a contest on Codechef. The contest is being organised by Programming Club IIT Kanpur. This is our second monthly contest. It is a 5 hours long "Individual" contest scheduled to start at 19:00 IST on 21/01/2015 (Wednesday) check [here](http://www.timeanddate.com/worldclock/fixedtime.html?msg=Monthly+Programming+Contest+%232+%2C+by+Programming+Club+IIT+Kanpur+&iso=20150121T19&p1=54&ah=5) for the exact time for you. The contest has been prepared by me , [user:triveni,2015-01-19] and [user:patch_adams,2015-01-19]. We would also like to thank [user:i_lost_my_handle,2015-01-19] for helping us prepare this round. You can see the previous contest here : http://www.codechef.com/WPC1401 <br> Contest link is : http://www.codechef.com/WPC1501 Top 8 student performers Globally and 7 from IIT Kanpur will get Codechef Goodies :) Expecting a grand participation! Hope you will enjoy the problems ! Best of Luck an...

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Invitation to HackerEarth August Circuits '18 Hello everyone! I would like to invite you to participate in HackerEarth monthly long contest [August Circuits 2018](https://www.hackerearth.com/challenge/competitive/august-circuits-18/). It has already started on 17th August 2018 and will run for 9 days. The problem set consists of 7 traditional algorithmic tasks of various difficulties and 1 approximate problem. For traditional algorithmic tasks, you will receive points for every test case your solution passes, so you can get some points with partial solutions as well. For the approximation task, your score depends on the best solution in the contest so far. Please check the contest page for more details. The problems have been prepared by the users: [user:.AJ.,2018-08-17], [BishalG](https://www.hackerrank.com/BishalG), [user:bciobanu,2018-08-17], [user:flash_7,2018-08-17] and me. The problems have been tested by [user:zscoder,2018-08-17] and [user:.AJ.,2018-08-17]. We have tried our best to ensure a really good contest for...

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Ad Infinitum August'14 -- HackerRank Hi! Ad Infinitum is back with [Infinitum August'14](https://www.hackerrank.com/infinitum-aug14), a monthly contest restricted to mathematics domain, held on HackerRank. Register at https://www.hackerrank.com/infinitum-aug14 The contest commences [on 14^th August 15:30 UTC](http://www.timeanddate.com/worldclock/fixedtime.html?msg=%5BHackerRank%5D+Ad+Infinitum+August%2714&iso=20140814T1530&p1=1440). You are allowed to enter the contest anytime, for tie breaking the timer will start when you view the challenge, which allows you to start late at your convenience, but once started try to finish as fast as possible to be on top of the leaderboard :) It's a 3 days contest with 8 problems (3 Easy, 3 Medium, 2 Hard) Scoring Distribution: 20 20 20 40 60 80 100 120 problem statements in English, Russian and Chinese **Top 10 on leaderboard gets Cool HackerRank T shirt,** **Update**: Everyone with full score will get a T shirt :D **Contributers** [user:ke...

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Infinitum May'14 -- HackerRank Hi! Ad Infinitum is back with [Infinitum May'14](https://www.hackerrank.com/infinitum-may14), a monthly contest restricted to mathematics domain, held on HackerRank. Register at https://www.hackerrank.com/infinitum-may14 Contest starts at [Saturday, 24 May 0530 GMT](http://www.timeanddate.com/countdown/generic?p0=438&iso=20140524T11&msg=Infinitum%20May%2714) It's a 2 day contest with 8 problems (3 Easy, 3 Medium, 2 Hard) Scoring Distribution: 20 20 20 40 60 80 100 120 problem statements in English, Russian translations by [user:romanova,2014-05-21] and Chinese translations by [user:wanbo,2014-05-21]. You can view the last month's challenges here: [March](https://www.hackerrank.com/infinitum-mar14/challenges), winner [user:dreamoon,2014-05-21] [April](https://www.hackerrank.com/infinitum-apr14/challenges), winner [user:Ulziisaihan,2014-05-21] **Top 10 on leaderboard gets Cool HackerRank T shirt** **Problem Setters** [user:Anton_Lunyov,2014-05-21] ...

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Ad Infinitum July'14 -- HackerRank Hi! Ad Infinitum is back with [Infinitum July'14](https://www.hackerrank.com/infinitum-jul14), a monthly contest restricted to mathematics domain, held on HackerRank. Register at https://www.hackerrank.com/infinitum-jul14 The contest commences [on 11^th July 15:30 UTC](http://www.timeanddate.com/worldclock/fixedtime.html?msg=%5BHackerRank%5D+Ad+Infinitum+July%2714&iso=20140711T1530&p1=1440). You are allowed to enter the contest anytime, for tie breaking the timer will start when you view the challenge, which allows you to start late at your convenience, but once started try to finish as fast as possible to be on top of the leaderboard :) It's a 2 day contest with 8 problems (3 Easy, 3 Medium, 2 Hard) Scoring Distribution: 20 20 20 40 60 80 100 120 problem statements in English, Russian and Chinese **Top 10 on leaderboard gets Cool HackerRank T shirt** **Contributers** [user:kevinsogo,2014-07-11] [user:OoO000oOOOoOooOo,2014-07-11] [user:bid...

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Invitation to SmallForces Monthly Contest #1 Hello, Coders! We are glad to announce that we are up with our first contest, [SmallForces Monthly Contest #1](https://codeforces.me/contestInvitation/fb4799002bc549837234aa5eff40fd40f63ee29b), which is all set to take place on [contest_time:437445]. **Registrations are now open.** You will have 120 minutes to solve 7 problems. - Problems are prepared by [user:jalppatel1428,2023-04-17] and [user:vasu_,2023-04-21]. - We would like to thank our special testers [user:zxy0909,2023-04-17] and [user:preet_25,2023-04-17]. - We would also like to thank our other testers [user:naisheelpatel,2023-04-17] and [user:hara108,2023-04-17]. We strongly recommend you to read all the questions once. We hope you will show your support by participating in maximum numbers and upvote the blog, so that it can reach to maximum number of people. Link to the SmallForces group: [Link](http://codeforces.me/group/R28ntkjari/blog)

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Infinitum June'14 -- HackerRank Hi! Ad Infinitum is back with [Infinitum June'14](https://www.hackerrank.com/infinitum-jun14), a monthly contest restricted to mathematics domain, held on HackerRank. Register at https://www.hackerrank.com/infinitum-jun14 The contest commences [on 13^th June 15:30 UTC](http://www.timeanddate.com/worldclock/fixedtime.html?msg=%5BHackerRank%5D+101+Hack+June+Edition&iso=20140613T1530). You are allowed to enter the contest anytime, for tie breaking the timer will start when you view the challenge, which allows you to start late at your convenience, but once started try to finish as fast as possible to be on top of the leaderboard :) It's a 2 day contest with 8 problems (3 Easy, 3 Medium, 2 Hard) Scoring Distribution: 20 20 20 40 60 80 100 120 problem statements in English, Russian and Chinese **Top 10 on leaderboard gets Cool HackerRank T shirt** **Problem Setters** [user:OoO000oOOOoOooOo,2014-06-12] [user:xorfire,2014-06-12] [user:darkshadows...

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[FEATURE REQUEST] Because old is gold. I am regularly giving contests on codeforces for the last few months now, and I have started to see how problem setters always try to come up with something new which most of the people will see for the first time. It's a good thing but sometimes the problem actually goes far away from anything that would make sense due to the added complexities. Whereas some problems although they have appeared somewhere else, actually teach some serious stuff to the person who saw it for the first time. So, my request is to come up with some weekly/monthly(as you wish) old classic contest or practice gym which would feature problems that teach something to newcomers and would be a nice refresher for the old OGs. I know there are a bunch of platforms already doing this but codeforces has it's own legacy when it comes to anything around competetive programming, so this would be a nice thing. If these contests are made rated, I agree that rating or color will lose relevance as there will be...

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DMOPC '20 June Contest Hi Codeforces, This weekend, we will be hosting the seventh and final DMOJ Monthly Open Programming Competition (DMOPC) of the 2020-2021 season on [DMOJ](https://dmoj.ca/). The contest will have a $3$ hour window and consist of $6$ problems with a difficulty we expect to be harder than Div. 2 contests but easier than normal Div. 1 contests. You can check out the contest page here for further details: https://dmoj.ca/contest/dmopc20c7 I encourage you to check out some of our [past problems](https://dmoj.ca/problems/?search=dmopc20c6) to get a feeling for what the contest might look like. Hope to see you there!

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CodeChef intellectual property rights? What is the IP governing for their regular contests like Lunchtime, Cook-off and monthly Challenges? For example, here at CodeForces it is defined at http://codeforces.me/blog/entry/4088 &mdash; see the Intellectual Property section: ~~~~~ 1. The rules below are used each time if for a particular round there are no separate rules. Competitors retain ownership of all intellectual and industrial property rights (including moral rights) in and to Submissions. 2. As a condition of submission, Competitor grants Codeforces, its subsidiaries, agents and partner companies, a perpetual, irrevocable, worldwide, royalty-free, and non-exclusive license to use, reproduce, adapt, modify, publish, distribute, publicly perform, create a derivative work from, and publicly display the Submission. 3. Contestants provide submissions on an "as is" basis, without warranties or conditions of any kind, either express or implied, including, without limitation, any warranties or conditions of title, non-...

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Problems that I Authored So Far Hi everyone! As we're reaching the end of this year and as AI becomes smarter, I'd like to write such a blog, motivated by similar blogs [by](https://codeforces.me/blog/entry/108940) [user:adamant,2024-12-22], [by](https://codeforces.me/blog/entry/108595) [user:tibinyte,2024-12-22], [by](https://codeforces.me/blog/entry/113093) [user:antontrygubO_o,2024-12-22], [by](https://codeforces.me/blog/entry/113720) [user:wuhudsm,2024-12-22], [by](https://codeforces.me/blog/entry/113687) [user:xiaowuc1,2024-12-23], [by](https://codeforces.me/blog/entry/113213) [user:jqdai0815,2024-12-23], [by](https://codeforces.me/blog/entry/118825) [user:TheScrasse,2024-12-23] and [by](https://codeforces.me/blog/entry/127391) [user:satyam343,2024-12-22]. I am a member of the [SUA Programming Contest Problem Setter Team](https://sua.ac), so most of the problems I authored are for the onsite contests prepared by our team. I would like to thank all our team members for discussing the problems with me, ...

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MathMash — Problem of the Day Hello Codeforces! <br> <br> Since many of our users participate in MathMash contests after viewing the contest announcement in Codeforces, I thought I should also put this news here. <br> <br> We're working on an update for the site. The design is ready. Now for the coding part, since I know how the site works under the hood I have to do most of it and organising the weekly contests alongside is making it really hard to do fast progress in the development. Preparing the problems, verifying their answers, setting up everything in the server, watching over the contest and finally writing the editorials take up 2 days at the least each week. It's also hard to keep focus in work with these regular intermissions. So I talked with the admins and we decided that it's better to give the contests a few weeks break and release the new site as soon as possible. We planned a lot of new features like monthly tournaments, reward system(where you get to exchange virtual points for real presents...

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TLE '16 November Contest [Announcement]  Hello Codeforces! [user:--d,2016-11-16], [user:nathanlo99,2016-11-16], [user:kobortor,2016-11-16], and I would like to invite everyone to write the Trudeau Logic Evaluation (TLE) 2016 November contest. The TLE is a monthly contest series written by high school students, predominantly from Pierre Elliott Trudeau High School, Canada. The contest serves as preparation for OI-style contests such as the CCO (Canadian Computing Olympiad) and IOI (International Olympiad in Informatics). The contest will be hosted on the [DMOJ](https://dmoj.ca) platform. The contest will consist of 6 problems, and the problem difficulty will range from Div. 2 A to Div. 1 D. Only problems 4, 5, and 6 will have pretests, and partial points (in the form of subtasks) will be awarded! The contest window will be 11...

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A scholarship for programming contestants — Jagiellonian University in Kraków, Poland Hello, This is a post for high school students who are considering their university options: [Jagiellonian University in Kraków](https://en.uj.edu.pl/en) has a [scholarship](https://matinf.uj.edu.pl/en_GB/kandydaci/oferta-dla-najlepszych/stypendium-mertensa/informacje) for talented students who want to study with us, aimed specifically at programming and/or mathematical contest medalists (this includes IOI, of course, but also your national competitions). We are one of the oldest (over 600 years!) European universities, with strong mathematical traditions. As for more modern times, we are regular ICPC World Finals qualifiers (with some [medals](https://icpc.global/community/results-2006) on our [record](https://icpc.global/community/results-2011), [too](https://icpc.global/community/results-2013)), and we tend to create [nice programming contests](https://codeforces.me/gym/100543) (also, [here](https://amppz.tcs.uj.edu.pl/2019/data/amppz-en.pdf) and [here](https://codeforces.com...

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Participate in HackerEarth's October Clash Contest Hello everyone, I want to invite all of you the next edition of one of the monthly contests on [HackerEarth](www.hackerearth.com )- this particular challenge for the month of October is called the October Clash. The duration for the same being 12 hours, consisting of 5 problems, of various difficulty levels. 1 Medium, 3 Hard, and 1 Challenge problem to keep you occupied for 12 hours. You can register for the contest at: [October Clash](http://www.hackerearth.com/october-clash/)- Let's see all of you here to make the contest bigger and solve some really mind boggling problems as one of the perks. Problem Setters: [Lokesh Khandelwal](http://codeforces.me/profile/phantom11),[Prateek Gupta](http://codeforces.me/profile/Xsquare),Sunny Agarwall,Swapnil Mehta Editorialist : [Lokesh Khandelwal](http://codeforces.me/profile/phantom11) Date : 18 October,2014 Time : [check time in your timezone](http://www.timeanddate.com/worldclock/fixedtime.html?msg=October%20Clash&iso=2014-...

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