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You can use several words in query to find by all of them at the same time. In addition, if you are lucky search understands word forms and some synonyms. It supports search by title and author. Examples:

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1.

The

Last visit:  3 years ago
Registered:  11 years ago
 
 
 
 
2.
By YouKn0wWho, 4 weeks ago, In English
The Ultimate Topic List (with Resources, Problems and Templates) This post took $4$ years to make. And this is the most significant thing that I have ever shared in my whole life. #### Story Hi, I have been doing CP for like $4$ years and from the very beginning what I have been feeling is a need for a comprehensive topic list that will contain all sorts of topics from easy to advanced with corresponding tutorials, problem lists and templates so that I wouldn't have to look at different sites, from here to there. So what do you do when you think something is missing from the world? Yeah, you create that thing! So here I am, sharing the ultimate topic list that you will need in CP. When I say that it took me $4$ years to make it, I genuinely mean it. I have been collecting them from the inception of my CP journey and yesterday I thought that it got its almost complete shape. You may not imagine the sheer excitement hidden under each of the characters of this post. #### Payment You can pay me just by upvoting this blog and by being a bet...

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3.
By rng_58, history, 10 months ago, In English
Retiring from competitive competitive programming Recently, I feel I've passed my peak as a competitive programmer, and ran out of sufficient energy/motivation to keep the top form and be prepared to win the next contest. I think I've done everything I can do as a competitive programmer, and now it's time to end my career as a professional (mind) sport player. It was a great experience. I'd like to thank everyone involved in the community, especially: - Competitors. It was always nice to compete against you all! - Problem writers who gave great problems to the community. I started my career as a competitive math-puzzle solver in 1999. The first contest was a local one named "junior sansu (arithmetic) olympiad". Since then, I enjoyed this sport a lot for 21 years. In 2007, I started TopCoder, and it changed my life. The problems were great, and every single match of SRM felt like a once-in-a-life event. A lot of legends were competing there — [user:Petr,2020-12-31], [user:tomek,2020-12-31], [user:ACRush,2020-12...

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4.
By tourist, history, 2 years ago, translation, In English
Codeforces Global Round 5 <img src="/predownloaded/2e/e2/2ee2f0f95f05aae6ca6f47812dae2dc2aabf277b.png" style="width:200px; float:right; margin: 0 1em 1em 1em"/> Hey! On [contest_time:1237] we will host [contest:1237]. It is the fifth round of a new series of [Codeforces Global Rounds](https://codeforces.com/blog/entry/65002) supported by XTX Markets. The rounds are open for everybody, the rating will be updated for everybody. The round will last for 2 hours 30 minutes, 8 problems are waiting for you, and one of them will be proposed in two versions. Scoring distribution: **500 &mdash; 750 &mdash; (750 + 750) &mdash; 2000 &mdash; 2500 &mdash; 3000 &mdash; 3750 &mdash; 4000** The prizes for this round: - 30 best participants get a t-shirt. - 20 t-shirts are randomly distributed among those with ranks between 31 and 500, inclusive. The prizes for the 6-round series in 2019: - In each round top-100 participants get points according to the [table](https://pastebin.com/QT5sXEaT). - The fi...

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Announcement of Codeforces Global Round 5
 
 
 
 
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5.
By MikeMirzayanov, 2 years ago, translation, In English
About the Failed Round 591/Technocup 2020 — Elimination Round 1 Hi Codeforces! Unfortunately, ill-wishers thwarted the round by making DDOS on our infrastructure. Neither the coordinator nor the writers of the round are subjects to blame for the failure. Please do not downvote the announcement of the round. I think that this situation is an additional reason to support the writers. They worked hard and prepared good problems! Apparently, such an attack should be regarded as a symptom of the fact that Codeforces outgrew the youth phase and entered serious adult life. Of course, we will respond with adequate measures to protect ourselves from such incidents. Fortunately, for almost 10 years of work, a large community has formed around those who care about Codeforces. We are not worried about possible additional expenses or efforts. We can do this. The rounds must go on. &mdash; [user:MikeMirzayanov,2019-10-06] **UPD 1:** All three of today's rounds will be unrated. **UPD 2:** Hooray! Today we've survived another DDOS attack. The round ...

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6.
By MikeMirzayanov, 17 months ago, In English
Codeforces: Soon We Will Change the Rating Calculation for New Accounts Hello everyone. In the coming days I will finish the implementation of small changes in the rating calculation for new accounts. Here are the main innovations. * The rating of the new account will be equal to $0$ for display (but it will be equal to $1400$ when calculating rating changes). * Suppose, after the first round, the participant gained $d_1$ rating points (remember that the rating was considered equal to $1400$ in such calculations), then in the rating display after this round $500+d_1$ will be displayed. Thus, after the first participation, the rating is likely to increase from $0$ to a value in the region of $500$ (plus or minus $300$ approximately). * Thus, before the second participation, the displayed rating is $500+d_1$, and the rating for calculating changes is $1400+d_1$. Suppose a new change is $d_2$, then the displayed rating becomes $500+d_1+350+d_2$. * Thus, before the third participation, the displayed rating is $500+d_1+350+d_2$, and the rating for calc...

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7.
By MikeMirzayanov, 18 months ago, In English
Codeforces Round #639: the round is rescheduled Hello, Codeforces! Unfortunately, I report that I decided to reschedule this round. I'm afraid that something might go wrong. Some strange database behavior has appeared, which leads to slow operation in completely unexpected places (it never was and should not be). I will work hard to fix it. My recent tests show that this can dramatically increase judging time (and leads to a huge queue). I don't want to risk the efforts of the writer, the coordinator, testers, and your time. Sorry about it, I was trying to fix it for many hours but I need more time. Hope it will be a great round! Mike. **UPD 1:** I temporarily rescheduled it on May, 6. But I'll discuss the date with the writer and coordinator and reschedule it again to the date they want. **UPD 2:** [user:Monogon,2020-05-04] approved that [contest_time:1345] is good new date and time for the round. See you in 3 days! **UPD 3:** It seems I've fixed the issue. It turned that it was connected with [week ago incident](htt...

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8.
By geranazavr555, history, 8 months ago, translation, In English
User activity in the profile! [new, Feb. 2021] For example, [user:tourist,2021-02-16], you can find it on his profile page: ![tourist](/predownloaded/f1/b7/f1b73bae1030397aef853c9907bf436c31af8836.png)

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9.
By MikeMirzayanov, 3 years ago, translation, In English
Codeforces: Problem Difficulties Hi Codeforces! Meet a small innovation on Codeforces &mdash; difficulties of problems (and at the same time a new widget filtering problems in the archive). For all the problems of the archive, I’ve calculated the difficulties in the scale of the rating of participants. Approximately this means that if the rating of the problem is equal to yours, then on a typical round you would solve the problem with a probability of 0.5. And, in general, if your rating is $r_i$, and the problem rating is $r_j$, then the problem during the round can be solved approximately with probability: $$P_{i,j}=\frac{1}{1+10^{\frac{r_j-r_i}{400}}}.$$ For example, if the rating of a problem is less than yours by 200, then the expected probability of solving the problem is 0.75. With a difference of 400 rating points, the probability increases to 0.9. For convenient search of problems in the archive, you can now use a special widget: <center><img src = "/predownloaded/1c/fb/1cfba40476423720c79f0f...

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10.
By 1-gon, history, 7 months ago, In English
Codeforces Round #712 omg hi! I am pleased to invite you to participate in [contest:1503] and [contest:1504]! You will be given **6 problems** and **2 hours 15 minutes** to solve them. I'm happy to announce the theme of this round is déjà vu! I would like to thank the following people: - <a class="rated-user user-red" href="https://images.emojiterra.com/twitter/512px/1f921.png" title="The Entire Circus">antontrygubO_o</a> for accepting all of my problems <span style="color:white;">at gunpoint</span> - <a class="rated-user user-orange" href="/profile/Nika_Tamliani" title="Useless Tester Nika_Tamliani">Nika_Tamliani</a>, <a class="rated-user user-violet" href="/profile/arvindr9" title="Useless Tester arvindr9">arvindr9</a>, <a class="rated-user user-red" href="/profile/dorijanlendvaj" title="Useful Tester dorijanlendvaj">dorijanlendvaj</a>, <a class="rated-user user-blue" href="/profile/I_Love_YrNameCouldBeHere" title="Useful Tester I_Love_YrNameCouldBeHere">I_Love_YrNameCouldBeHere</a>, <a class="r...

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11.
By Ari, 16 months ago, In English
Codeforces Global Round 9 <img src="/predownloaded/2e/e2/2ee2f0f95f05aae6ca6f47812dae2dc2aabf277b.png" style="width:200px; float:right; margin: 0 1em 1em 1em"/> Hi! On [contest_time:1375] we will host [contest:1375]. It is the third round of a 2020 series of [Codeforces Global Rounds](/blog/entry/65002). The rounds are open and rated for everybody. The prizes for this round: - 30 best participants get a t-shirt. - 20 t-shirts are randomly distributed among those with ranks between 31 and 500, inclusive. The prizes for the 6-round series in 2020: - In each round top-100 participants get points according to the table. - The final result for each participant is equal to the sum of points he gets in the four rounds he placed the highest. - The best 20 participants over all series get sweatshirts and place certificates. Thanks to XTX, which in 2020 supported the global rounds initiative! The problems of this round were prepared by a team of authors: [user:adamant,2020-07-01], [user:anto...

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Announcement of Codeforces Global Round 9
 
 
 
 
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12.
By tourist, history, 4 years ago, translation, In English
Hello 2018 Hello 2018! If you're still thinking what to do on the eighth day of year 2018, pay attention! The first round for both divisions of the new year starts on January 8 at 17:35 Moscow time ([what about other timezones?](https://www.timeanddate.com/worldclock/fixedtime.html?msg=Hello+2018&iso=20180108T1735&p1=3396&ah=2&am=30)). Four important components of Hello 2018 will be the same as in Good Bye 2017: - Div1 + Div2 combined - 8 problems - 2 hours 30 minutes - Rated But there will also be a substantial difference: - Different problems The problems of this round have been proposed and prepared by [user:YakutovDmitriy,2018-01-06], [user:BudAlNik,2018-01-06] and myself. Thanks to everyone without whom this round wouldn't be possible as well: [user:AlexFetisov,2018-01-06], [user:Golovanov399,2018-01-08], [user:KAN,2018-01-06], [user:MikeMirzayanov,2018-01-06], [user:PavelKunyavskiy,2018-01-06], [user:qwerty787788,2018-01-06], [user:VArtem,2018-01-07], [user:winger,20...

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Announcement of Hello 2018
 
 
 
 
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13.
By MikeMirzayanov, 3 years ago, In English
Codeforces: Our Steps After DDOS Attack Hello. As I wrote into a comment, last round we are faced with a strong DDOS-attack which ruined the competition. I don't know who did it, I also don't know reasons to do it. I'm very upset about the situation and ready to make an effort to be prepared for such issues. I spend a lot of time to be ready for such incidents. Here are steps you need to do to be ready for unexpected failures: * Join our telegram channel by the link https://t.me/codeforces_official to read urgent news. * Be sure that you know the password of your Codeforces account. If you don't remember it, just use <a href="https://codeforces.com/passwordRecovery">the password recovery feature</a>. Please, do it right now. * I've implemented a minimalistic website for replacing the main site in case of emergencies. Now you can only read problems, view your submissions (without any details), submit codes. Probably, later I'll add some more features, but anyway, the minimalistic version will have only vital fea...

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14.
By 1-gon, history, 18 months ago, In English
Codeforces Round #639 Hello, Codeforces! I'm very glad to invite you to [contest:1344] and [contest:1345]. This contest will take place on [contest_time:1344]. In both divisions, you will have **2 hours 15 minutes** to solve **6 problems**. The score distribution will be announced closer to the start of the contest. Of course, this round would not be possible without the help of many people, who I'd like to thank: - [user:isaf27,2020-05-01], for coordinating this round, and helping with solution ideas. - My ICPC teammates [user:Kuroni,2020-05-01] and [user:strongoier,2020-05-01], and coach [user:cn355,2020-05-01], for encouraging me to pursue competitive programming. In particular, I'd like to thank [user:Kuroni,2020-05-01] for being so spectacularly bad that a barely-orange user like myself actually has a place on our team. - [user:300iq,2020-05-01], [user:antontrygubO_o,2020-05-01], [user:Ari,2020-05-01], [user:ffao,2020-05-01], [user:fpc_coder,2020-05-01], [user:gamegame,2020-05-01], [user:Kur...

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15.
By MikeMirzayanov, 16 months ago, In English
Codeforces EDU: β-testing (Now in English!) <img src="/predownloaded/47/86/4786c2ec901c0b5b490794ca6fd5145f0dcdeae3.png" style="float:right; width: 400px; margin: 0 1em 1em 1em"/> Hello Codeforces! In February, in the Russian-language interface, we announced a new educational subsection of the website. It's time to go international! I am pleased to invite you to test the new section, which so far has the working title EDU. I hope that someday EDU will become a real educational hub for fans of programming competitions. It will be great to have in one place the collected educational content with text and video materials, with selected thematic problems. At the moment, its functionality is still under development, and here is the current progress and <i>β</i>-testing preview. Write your comments and suggestions in the comments here. <center style="margin:2.5em;"> <a href="/edu/courses" style="text-decoration:none; font-size:18px; background-color:#01579B; color:white; font-weight:bold; padding:0.5em 1em;">Go to EDU ...

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16.
By YouKn0wWho, 3 months ago, In English
Codeforces Round #735 (Div. 2) কি অবস্থা মামা? (That's Bengali for "What's up dude?") I am super excited to invite you to participate in [contest:1554] which will be held on [contest_time:1554]. This round is rated for future LGM participants whose current rating is $\le 2099$. You will be given $5$ problems and $2$ hours to solve them. All the problems are authored and prepared by me. I would like to thank - - [user:antontrygubO_o,2021-07-20] for his awe-inspiring coordination of the round <i style="color:White;"> and rejecting my problems, and thus hurting my feelings.</i> - [user:Um_nik,2021-07-20], [user:_Ash__,2021-07-25], [user:Anachor,2021-07-20], [user:Arg_007,2021-07-20], [user:Alpha_Q,2021-07-20], [user:DAleksa,2021-07-20], [user:steinum,2021-07-20], [user:tasdid,2021-07-20], [user:border,2021-07-20], [user:mk_Shahriar,2021-07-20], [user:t17,2021-07-20], [user:imAnik,2021-07-20], [user:Alfeh,2021-07-20], [user:Aritra741,2021-07-20], [user:FrozenBlood,2021-07-20], [user:SajidZakaria,2021-07-20]...

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17.
By MikeMirzayanov, 22 months ago, In English
Goodbye 2019. Hello 2020! <img src="/predownloaded/85/58/8558df7ac8a1c33d501ea8fd9b18dd3d95886b90.png" style="width:290px; float:right; margin: 0 1.5em 1.5em 1.5em"/> I am happy to wish you a Happy New Year! I wish you a great, bright, interesting New Year! Just believe that it can become so: difficulties will be left behind, and ahead of you will be a joy of victories and discoveries. I wish all of us new interesting problems, records and achievements! Set new goals and be sure to try to achieve them! And do not go far, we will try to make your 2020 year more fun! I thank with all my heart for the contribution to the community of coordinators, problem writers, testers, and those who wrote interesting posts and comments. Many thanks to the sponsors, partners and customers: you help the community not to stand still, give the opportunity to hold interesting events. Thanks to all visitors to the website and just not indifferent. See you in the new year! &mdash; [user:MikeMirzayanov,2019-12-31]

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18.
By geranazavr555, history, 12 months ago, translation, In English
Streams on Codeforces Hello everyone! Today Codeforces got support for streams! Thanks [user:tourist,2020-10-21] for the great idea! There are two popular platforms supported: Twitch and YouTube. The opportunity to add streams to Codeforces is open to red participants and by individual invitations for now. We possibly open this opportunity to more users later. The idea is that streamers will be able to announce their streams to the Codeforces audience. To do this, you should add the stream to the site using a special section in your profile. Please, note that when adding a Twitch stream, you just need to specify the URL of your channel, and when adding a YouTube broadcast, its unique short link (URL like youtu.be/...) Shortly before the start of the stream, a notification about the upcoming stream will appear in the sidebar on the right, which will be shown to all site visitors. For example, right now there is a [user:Errichto,2020-10-21]'s stream announcement in the sidebar. ![Streams in ...

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19.
By tourist, 4 years ago, translation, In English
VK Cup 2017 Round 3 + Codeforces Round #412 (Div. 1 + Div. 2) Hi everyone! The last elimination round of VK Cup 2017, Round 3, will take place on May 7 at 18:35 MSK ([check your timezone here](https://www.timeanddate.com/worldclock/fixedtime.html?msg=VK+Cup+Round+3&iso=20170507T1835&p1=352&ah=3)), along with separate Codeforces Round #412 for both divisions. All three rounds will be three hours long, and all three rounds will be rated. The contest "VK Cup 2017 — Round 3" is for teams qualified from Round 2 or Wildcard Round 2. The top 20 teams will advance to the final which will be held in July 2017 in Saint Petersburg! Huge thanks to [user:KAN,2017-05-06], [user:qwerty787788,2017-05-06], [user:PavelKunyavskiy,2017-05-06], [user:AlexFetisov,2017-05-07], [user:MikeMirzayanov,2017-05-06], and VK company for making this round possible. Codeforces will be the main character of most problems. Don't forget that it's useful to read the statements of all the problems. Good luck! As we're in year 2017, the scoring will obviously be stat...

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Announcement of VK Cup 2017 - Round 3
 
 
 
 
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20.
By MikeMirzayanov, 10 months ago, In English
Goodbye 2020. Hello 2021! <img src="/predownloaded/f4/1f/f41ff0beb745fb2f84a55d9f2cc451273efc6267.jpg" style="width:300px; float:right; margin: 0 1em 1em 1em"/> Hello Codeforces! This unusual and difficult 2020 has come to an end! What will the new year be like? I wish all of us that we have the opportunity to meet in person so that the contests take place not only online. I ask you to think of something important and good. Let this wish come true! We have had a large number of rounds this year. I hope we have pleased you with interesting problems. Thanks to the round coordinators and writers! You make our community richer. Please make us happy in 2021! I wish the participants victories over yourself (and over problems!) and development of your skills, interest and curiosity! Hello, 2021! And we have traditional gifts! #### <img src="https://assets.codeforces.com/images/wand.png"/> Change Handle Feature Hurry! Only until the 10th of January, you can change your handle (<b>but only onc...

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21.
By MikeMirzayanov, 5 years ago, translation, In English
About the Round 382 Good afternoon! I've decided to share my thoughts on the round 382. Of course, it turned upset not only to me, but also to the round coordinator [user:GlebsHP,2016-11-28]. In this round the main negative feedback were caused by two problems: [problem:735D] and [problem:735C]. Regarding [problem:735D]. I do not share the criticism to this problem. In fact, to solve it would be nice to be familiar with <a href="https://en.wikipedia.org/wiki/Goldbach&apos;s_conjecture"> Goldbach's Conjecture</a> and better with <a href="https://en.wikipedia.org/wiki/Prime_number_theorem">Prime Number Theorem</a>. These facts are medium-popular in the world of programming contests. Familiarity with them is useful, gives useful insight into primes. It is important: in this problem it was necessary to perform a simple, but nevertheless, additional step to find solution. It seems to me that it's okay to use problems that have a reduction to some popular and semi-popular topics. Otherwise, it is th...

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22.
By MikeMirzayanov, 3 years ago, translation, In English
Codeforces: Updates in rating and rounds <img src="/predownloaded/21/a3/21a33b497ee8a34a678befc3f79745eb69a9cf07.png" style="float:right; margin: 0 1em 1em 1em;"/> Hello, Codeforces! It's time for news. I hope you will enjoy! * We reduce the rating bound for the orange color. Thus, now the orange rating (and the _Master_ title) will start from 2100 rating units. * The lower bound of the rating for _legendary grandmasters_ is increased to 3000 rating units. Thus, right now in the community, 14 participants meet this requirement. Real legends! * For rounds like "Div. 2 Only" the upper bound of the rating for official participation is increased. Now everyone whose rating is less than 2100 (i.e., before _masters_) will be able to register for such rounds to participate officially, their rating will be updated based on the results of the round. We do not plan to increase the complexity of Div. 2 rounds. Practice shows that the problems of such rounds are interesting and useful for participants "below the orange". ...

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23.
By YouKn0wWho, 5 weeks ago, In English
(The Ultimate) Code Library Hey everyone, I am sharing my personal code library where I compiled **almost all** the important templates that you will need in CP (saying almost just for courtesy). Most of the codes are originally written by me and some of them are collected from others but modified in a cleaner way. Link: [https://github.com/ShahjalalShohag/code-library](https://github.com/ShahjalalShohag/code-library) It took me around 4 years to complete the list. Maybe each line is just a line to you but to me it tells a story of the excitements I had while learning those stuffs, the sleepless but fun nights I had to seek knowledge. ###### Why am I sharing this library? - Just so that your learning path becomes a bit smoother. - Knowledge hidden inside my head or codes in a private code-library will be useless when I am dead, so it's better to share those among people before I die. Also, you can make me happy(as in to pay me) just by upvoting this blog and giving a star to the repository. I beli...

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24.
By Radewoosh, history, 3 years ago, In English
Hello 2019 Hello coders! I hope that you are enjoying the New Year as much as me. To make its beginning even greater, Codeforces is going to host a contest and I will be an author of all tasks. Hello 2019 will take place on [Friday](https://www.timeanddate.com/worldclock/fixedtime.html?day=4&month=1&year=2019&hour=17&min=35&sec=0&p1=166). Using the opportunity, I want to thank to: - [user:lewin,2019-01-02] and [user:mnbvmar,2019-01-02] for testing the round. - [user:mnbvmar,2019-01-02] for indescribably helpful discussions about problems. - [user:_kun_,2019-01-02] and [user:KAN,2019-01-02] for round coordination and help with preparation. - [user:MikeMirzayanov,2019-01-02] for such great platforms (you know which ones :P). The round will consist of 8 problems and you will be given <s>two and a half</s> three hours to solve them. Yes, the round will be **rated**. There will be no interactive problems, but if you want you can read [this](https://codeforces.com/blog/entry/45307) docum...

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Announcement of Hello 2019
 
 
 
 
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25.
By Sooke, 18 months ago, In English
Codeforces Round #635 _Riichi...Tsumo! 2 han 2000 points!_ ![ ](/predownloaded/a9/4f/a94f898a1c9c906cd81ecd483c3ec9ff5e6315c0.png) Hi! Have you ever heard of the game called _Mahjong Soul_? It is a Japanese Mahjong game that is famous for the adorable characters. We are excited to invite you to take part in [Codeforces Round #635](https://codeforces.com/contests/1336,1337), where you can help the characters in trouble. This round will be held on [contest_time:1336]. Most importantly, it is **rated** for both divisions! Each division will be given **6 problems** and you will have **2.5 hours** to solve them. An interactive problem may be found in this round. If you are not familiar with interactive problems, you can learn about them [here](https://codeforces.com/blog/entry/45307). The problems were prepared by [user:EternalAlexander,2020-04-14], [user:ustze,2020-04-14] and me [user:Sooke,2020-04-14]. We sincerely thank [user:isaf27,2020-04-14] for reviewing and coordinating the round, and ...

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26.
By Vladik, 13 months ago, translation, In English
Petition on the flag of Belarus Greetings to all belarusians who actively, or not so actively, participate in this amazing community we have on Codeforces. I would like to ensure that we have your support to initiate changing the flag of Belarus on this website to the historical [white-red-white flag](https://ru.wikipedia.org/wiki/%D0%91%D0%B5%D0%BB%D0%BE-%D0%BA%D1%80%D0%B0%D1%81%D0%BD%D0%BE-%D0%B1%D0%B5%D0%BB%D1%8B%D0%B9_%D1%84%D0%BB%D0%B0%D0%B3), since the current official flag of Belarus has become strongly associated with crimes against humanity, with the brutality, torture, ferocity and human rights abuses which have, sadly, become commonplace in the past few months in our beautiful country. <html> <body> <img src="https://upload.wikimedia.org/wikipedia/commons/thumb/5/50/Flag_of_Belarus_%281918%2C_1991%E2%80%931995%29.svg/500px-Flag_of_Belarus_%281918%2C_1991%E2%80%931995%29.svg.png" style="display: block; width:30%; margin: 0 auto; border: 1px solid black"> </body> </html> Outside of public ...

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27.
By 1-gon, history, 15 months ago, In English
Codeforces Round #658 Hello, Codeforces! I'm very glad to invite you to [contest:1381] and [contest:1382]. This contest will take place on [contest_time:1381]. In both divisions, you will have **2 hours** to solve **5 problems** (and one subtask). The score distribution will be announced closer to the start of the round. Huge thanks to: - [user:isaf27,2020-07-19] for excellent coordination of this round - [user:Andreii,2020-07-19], [user:antontrygubO_o,2020-07-19], [user:Ari,2020-07-19], [user:DeadlyCritic,2020-07-19], [user:gamegame,2020-07-19], [user:growup974,2020-07-19], [user:hugopm,2020-07-19], [user:Kuroni,2020-07-19], [user:NooB_MB,2020-07-19], [user:Priyank,2020-07-19], [user:SecondThread,2020-07-19], [user:--Someone--,2020-07-19], [user:talibmohd,2020-07-19], [user:WNG,2020-07-19] for testing the problems and providing useful feedback. - [user:MikeMirzayanov,2020-07-19] for providing Codeforces and Polygon platforms. I've worked hard to ensure the pretests are short and the statement...

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