Codeforces Round #339 (Div. 1 & Div. 2) Hi all! In two days, at 19:35 MSK Codeforces Round #339 (Div. 1 & Div. 2) will take place. This is an unusual round since we — the problemsetters — are highschool students who participate in the programming training group at high school #179. This round is our first effort and we did our best to make it interesting and bug-free. I invite you all to compete in this round since the problems will be **solvable**, but even [user:tourist,2016-01-13] will have to think over some of them. :) With supervision and control from Mikhail Tikhomirov ([user:endagorion,2016-01-13]), the problems were developed by: Egor Chunaev ([user:ch_egor,2016-01-13]), Vasily Alferov ([user:platypus179,2016-01-13]), Dmitry Sayutin ([user:cdkrot,2016-01-13]), Timofey Gutor ([user:Tigutor,2016-01-13]), Maria Fedorkina ([user:MF2000,2016-01-13]). Mikhail Sorokin ([user:themikemikovi4,2016-01-13]) and Sergey Aleikin ([user:Derrior,2016-01-13]) contributed their problem ideas. We thank Gleb Evstropov ([user:Gl...

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Educational Codeforces Round 179 [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:2111] [contest:2111] 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 problems** and **2 hours** to solve them. Almost all of the problems in the round were invented and prepared by me. I would like to thank Ivan [user:BledDest,2025-06-...

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Codeforces Round #179 Hello everyone! Codeforces Round #179 will take place on [Thursday, April 11th at 19:30 MSK](http://timeanddate.com/worldclock/fixedtime.html?day=11&month=4&year=2013&hour=19&min=30&sec=0&p1=166). This is my fifth Codeforces round and I hope not the last. I'd like to thank [user:Gerald,2013-04-11] for helping me to prepare the round. Special thanks to [user:Delinur,2013-04-11] for translation of all problem statements into English. I strongly recommend you to read ALL the problems. Problems point values for 1 division will be **standart**. For the 2 division it will be: **500-1500-1500-2000-2500**. Gl & hf ! :) Contest is over. I hope that problems vere interesting for you. Division 1 winners: 1). [user:marcina007,2013-04-11] 2). [user:yeputons,2013-04-11] 3). [user:gawry,2013-04-11] 4). [user:KADR,2013-04-11] 5). [user:enot.1.10,2013-04-11] Division 2 winners: 1). [user:goie,2013-04-11] 2). [user:Koblyk,2013-04-11] 3). [user:Beri...

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Educational Codeforces Round 94 [Rated for Div. 2] Hello Codeforces! On [contest_time:1400] [contest:1400] will start. Series of Educational Rounds continue being held as [Harbour.Space University](https://harbour.space/) initiative! You can read the details about the cooperation between [Harbour.Space University](https://harbour.space/) and Codeforces in the <a href="http://codeforces.me/blog/entry/51208">blog post</a>. 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 problems** and **2 hours** to solve them. The problems were invented and prepared by Roman [user:Roms,2020-08-24] Glazov, Adilbek [user:adedalic,2020-08-24] Dalabaev, Vladimir [user:vovuh,2020-08-24] Petrov, Ivan [us...

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Codeforces Round #179 tutorial [problem:296A] Note that after applying the operations of the exchange, we can get any permutation of numbers. Not difficult to understand that the answer is "YES", if you can place a single number that it would not stand in the neighboring cells. Thus, if a some number is meeted C times, it must fulfill the condition C <= (n+1) / 2. [problem:296B] Будем решать обратную задачу: посчитать количество способов сделать сравнимые пары. Для начала посчитаем количество способов сделать первую строку меньше равной второй. Это количество равно произведению количества способов сделать это для каждой позиции по отдельности,так как они все позиции независимы. Посчитаем такую же величину, но когда вторая строка меньше-равна первой. И аналогично посчитаем количество способов сделать две строки равными. Для каждого символа величины можно считать простым циклом. Теперь возьмем величину 10 в степени количества знаков вопроса во входном файле и отнимем полученный ответ на обратную з...

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Codeforces Round #395 (Div. 1 + Div. 2) Ladies and gentlemen! Codeforces Round #395 for both divisions will happen tomorrow, on [Thursday, 2 February 2017 at 13:35 UTC](https://www.timeanddate.com/worldclock/fixedtime.html?msg=Codeforces+Round+%23395&iso=20170202T1335&p1=1440). Problems were prepared by me (Vasiliy Alferov) and students of Moscow school #179: [user:s17b2_voroneckij,2017-02-01] (Dima Voronetsky), [user:ilya_the_lamer,2017-02-01] (Ilya Pauzner) and [user:akvasha,2017-02-01] (Anton Kvasha). Also, [user:KAN,2017-02-01] (Nikolay Kalinin) is author of one of the problems. Invaluable help was given to us by Codeforces coordinator [user:KAN,2017-02-01] (Nikolay Kalinin). Thanks to [user:MikeMirzayanov,2017-02-01] (Mike Mirzayanov) for wonderful platforms Codeforces and Polygon. Also thanks to [user:Endagorion,2017-02-01] (Mikhail Tikhomirov), [user:winger,2017-02-01] (Vladislav Isenbaev), [user:AlexFetisov,2017-02-01] (Alex Fetisov) and [user:cdkrot,2017-02-01] (Dmitry Sayutin) for reading out our statement...

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Educational Codeforces Round 80 [Rated for Div. 2] Hello Codeforces! On [contest_time:1288] [contest:1288] will start. Series of Educational Rounds continue being held as [Harbour.Space University](https://harbour.space/) initiative! You can read the details about the cooperation between [Harbour.Space University](https://harbour.space/) and Codeforces in the <a href="http://codeforces.me/blog/entry/51208">blog post</a>. 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 problems** and **2 hours** to solve them. The problems were invented and prepared by Roman [user:Roms,2020-01-13] Glazov, Adilbek [user:adedalic,2020-01-13] Dalabaev, Vladimir [user:Vovuh,2020-01-13] Petrov, Ivan [user:Bl...

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Educational Codeforces Round 179 Editorial Thank you for participating! I hope you enjoyed the problems. [problem:2111A] Idea: [user:FelixArg,2025-06-04] <spoiler summary="Tutorial"> [tutorial:2111A] </spoiler> <spoiler summary="Solution (FelixArg)"> ~~~~~ #include<bits/stdc++.h> using namespace std; #define int long long void solve(){ int x; cin >> x; int ans = 0; int a1 = 0, a2 = 0, a3 = 0; while(min({a1, a2, a3}) < x){ if (a1 <= a2 && a1 <= a3){ a1 = min(a2, a3) * 2 + 1; } else if (a2 <= a1 && a2 <= a3){ a2 = min(a1, a3) * 2 + 1; } else{ a3 = min(a1, a2) * 2 + 1; } ans++; } cout << ans << '\n'; } signed main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); int tests = 1; cin >> tests; for (int test = 0; test < tests; test++){ solve(); } return 0; } ~~~~~ </spoiler> [problem:2111B] Idea: [user:FelixArg,2025-06-04] <spoiler summary="Tutorial"> [tutorial:2111B] </spoiler> <spoiler summary="Soluti...

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Experimental Educational Round: VolBIT Formulas Blitz Editorial #### [A. Again Twenty Five!](http://codeforces.me/problemset/problem/630/A) The problem of getting the last two digits is equivalent to the problem of getting the number modulo $100$. So we need to calculate $5^{n} \mod 100$. According to [cut] the rules of modular arithmetic $(a \cdot b) \mod c = ( (a \mod c) \cdot (b \mod c) ) \mod c$ So $5^{n} \mod 100 = ((5^{n-1} \mod 100) \cdot 5) \mod 100$ Let's note that $5^2=25$. Then $5^3 \mod 100 = ((5^2 \mod 100) \cdot 5) \mod 100 = (25 \cdot 5) \mod 100 = 25$ $5^4 \mod 100 = ((5^3 \mod 100) \cdot 5) \mod 100 = (25 \cdot 5) \mod 100 = 25$ And so on. All $5^n \mod 100$ are equal to $25$ for all $n \ge 2$. So to solve the problem one need to just output `25`. There is no need to read $n$. #### [B. Moore's Law](http://codeforces.me/problemset/problem/630/B) Every second the number is multiplied by $1.000000011$. Multiplication several times to the same number is equivalent to exponentiation. So the formula i...

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Educational Codeforces Round 82 [Rated for Div. 2] Hello Codeforces! On [contest_time:1303] [contest:1303] will start. Series of Educational Rounds continue being held as [Harbour.Space University](https://harbour.space/) initiative! You can read the details about the cooperation between [Harbour.Space University](https://harbour.space/) and Codeforces in the <a href="http://codeforces.me/blog/entry/51208">blog post</a>. 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 **7 problems** and **2 hours** to solve them. The problems were invented and prepared by Roman [user:Roms,2020-02-11] Glazov, Adilbek [user:adedalic,2020-02-11] Dalabaev, Vladimir [user:Vovuh,2020-02-11] Petrov, Ivan [user:Bl...

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Educational Codeforces Round 49 [Rated for Div. 2] On [contest_time:1027] Educational Codeforces Round 49 will start. Series of Educational Rounds continue being held as [Harbour.Space University](https://harbour.space/) initiative! You can read the details about the cooperation between [Harbour.Space University](https://harbour.space/) and Codeforces in the <a href="http://codeforces.me/blog/entry/51208">blog post</a>. This round will be **rated for the participants with rating lower than 2100**. It will be held on extented ACM 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 **7 problems** and **2 hours** to solve them. The problems were invented and prepared by Vladimir [user:Vovuh,2018-08-17] Petrov, Adilbek [user:adedalic,2018-08-17] Dalabaev, Ivan [user:BledDest,2018-08-17] Androsov, Mike [u...

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Educational Codeforces Round 78 [Rated for Div. 2] Hello Codeforces! On [contest_time:1278] [contest:1278] will start. Series of Educational Rounds continue being held as [Harbour.Space University](https://harbour.space/) initiative! You can read the details about the cooperation between [Harbour.Space University](https://harbour.space/) and Codeforces in the <a href="http://codeforces.me/blog/entry/51208">blog post</a>. 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 problems** and **2 hours** to solve them. The problems were invented and prepared by Roman [user:Roms,2019-12-18] Glazov, Adilbek [user:adedalic,2019-12-18] Dalabaev, Vladimir [user:Vovuh,2019-12-18] Petrov, Ivan [user:Bl...

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Lexington Informatics Tournament 2023 **Final update**: The contest has finished! This year, since it was prepared using Polygon, it is available for upsolving in the [Codeforces gym](https://codeforces.me/gym/104511). Thanks everyone for participating! And congratulations to the top teams: | Place | Team | Points | Penalty | | ----- | ---- | ------ | ------- | | 1 | [user:Golovanov399,2023-08-09], [user:andreysergunin,2023-08-09], [user:amethyst0,2023-08-09] | 850 | 177:51 | | 2 | [user:hyforces,2023-08-09], [user:lunchbox,2023-08-09], [user:oursaco,2023-08-09] | 850 | 179:52 | | 3 | [user:GusterGoose27,2023-08-09], [user:Ritwin,2023-08-09], [user:skittles1412,2023-08-09] | 830 | 171:40 | | 4 | [user:null_awe,2023-08-09], [user:PurpleCrayon,2023-08-09], [user:penguinhacker,2023-08-09] | 830 | 178:43 | | 5 | [user:antontrygubO_o,2023-08-09], [user:244mhq,2023-08-09] | 800 | 169:11 | **Update update**: Both the [Standard Round](https://lit.lhsmathcs.org) 5-day window and CTF Round have started. GOOD LUCK HA...

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Contests hack statistics (Number of hacks by round) Just felt like gathering some data about hacks. Parsed around ~400 last contests Probably it would be worth it to also include SFT, but whatever Educational 96 is not finished yet but also whatever Last 100 ------------------ **847** Educational Codeforces Round 96 (Rated for Div. 2) **30** Codeforces Global Round 11 **248** Codeforces Round #674 (Div. 3) **0** 2020 ICPC, COMPFEST 12, Indonesia Multi-Provincial Contest (Unrated, Online Mirror, ICPC Rules, Teams Preferred) **97** Bubble Cup 13 &mdash; Finals [Online Mirror, unrated, Div. 2] **86** Bubble Cup 13 &mdash; Finals [Online Mirror, unrated, Div. 1] **20** Codeforces Round #675 (Div. 2) **1** Codeforces Round #672 (Div. 2) **70** Codeforces Round #671 (Div. 2) **58** Educational Codeforces Round 95 (Rated for Div. 2) **3** Codeforces Round #673 (Div. 2) **11** Codeforces Round #673 (Div. 1) **73** Codeforces Round #667 (Div. 3) **121** Grakn Forces 2020 **4** Co...

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Topcoder Single Round Match 600 and Special Round Match 600.5: t-shirts Topcoder SRM 600 will be held next Saturday in [21:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=14&month=12&year=2013&hour=12&min=00&sec=0&p1=179) On round they promise 120 t-shirts for Div.1 and 40 t-shirts for Div.2, half for top ranked, and half the participants randomly chosen among having more zero points. But that's not all. On Sunday [21:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=15&month=12&year=2013&hour=12&min=00&sec=0&p1=179) there will be held non-rated SRM 600.5 (Special Round Match). Where there will be 40 more t-shits and 600$ prize for first place. Round will have duration of 4 hours and consists of two tasks, which did not give on-sight TCO as too complex and one Div1-Hard level. Besides the top 40 with a nonzero score promise 10 t-shirts for random spectators (people who were logged in the arena more than 3 hours of 4). **UPD**: Since this match TL and ML are indicated in the problem. The authors say that the...

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Lexington Informatics Tournament 2026 (New Format, Cash Prizes!) **FINAL UPDATE**: The contest is now over! The problems are available for upsolving in the [Codeforces gym](https://codeforces.me/gym/106637), and you can also read the editorial [here](https://hackmd.io/@C0DET1GER/Syl07aK-Bfl). Thanks for participating! And congratulations to the top teams (out of 1500 points): | Place | Team Name | Members | Points | Penalty | | ----- | --------- | ------- | ------ | ------- | | 1 | Segfault go BRRRR | [user:jeroenodb,2026-08-05], [user:BLOBVISGOD,2026-08-05], [user:Karuk,2026-08-05] | 1125 | 174:46 | | 2 | bwaaa | [user:reirugan,2026-08-05], [user:turska,2026-08-05], [user:catgirl,2026-08-05] | 1032 | 177:19 | | 3 | bribritt | [user:literalchild,2026-08-05] | 1025 | 171:00 | | 4 | bruhopen | [user:__jk__,2026-08-05], [user:p0tato,2026-08-05] | 1025 | 172:50 | | 5 | EtchedOffice | [user:amsraman,2026-08-05], [user:DylanSmith,2026-08-05], [user:BucketPotato,2026-08-05] | 1020 | 174:54 | As well as the top high-school teams: | Place ...

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Codeforces Round #248 Statistics [contest:434] and [contest:433] round statistics [cut] : ### Div. 1 #### First accepted: **A** (00:07) [user:Coder,2014-05-23] [user:mmaxio,2014-05-23] <br/> **B** (00:25) [user:RAVEman,2014-05-23] <br/> **C** (00:39) [user:daizhenyang,2014-05-23] <br/> **D** (01:32) [user:WJMZBMR,2014-05-23] <br/> #### Total hack attempts: +179:-71 #### Top-6 hackers: **1150** [user:MrDindows,2014-05-23] +12:-1 <br/> **1100** [user:Seyaua,2014-05-23] +13:-4 <br/> **1000** [user:qazwsxedcrfvtg14,2014-05-23] +10:-0 <br/> **1000** [user:fixme,2014-05-23] +10:-0 <br/> **900** [user:evader,2014-05-23] +9:-0 <br/> **900** [user:WanderingID,2014-05-23] +9:-0 <br/> #### Other info <br/> [Complete Results](https://lh4.googleusercontent.com/-LirEeqqu7sU/U4CKrvohmZI/AAAAAAAAB5A/Mj3Gy3yKUAA/s0/CF_248_1_2.png)<br/><br/> ![ ](https://lh4.googleusercontent.com/-Fw5Q9GcYerg/U4CKrmzVrWI/...

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WWPIT Spring 2025 Programming Contest Hey Codeforces! [West Windsor-Plainsboro Programming Competitions](https://wwppc.tech) is proud to announce the [**WWPIT 2025**](https://wwppc.tech/contest) (WWP Informatics Tournament)! It will start on **[Saturday, April 19th from 1:00 PM to 7:30 PM Eastern Time](https://www.timeanddate.com/worldclock/fixedtime.html?msg=WWPIT+Spring+2025&iso=20250419T13&p1=179&ah=7)**, open to all **online participants**. **Update, the contest has been moved to 1:00 PM Eastern Time to avoid intersecting with the Div. 1 + 2 round.** The competition will have **two rounds**: - Speed round: **$1$ hour** to solve **$8$ problems**. - Power round: **$3$ hours** to solve **$8$ problems**. There will be **two divisions**: - Novice: $\le$ Expert (AP CSA-USACO Silver) - Advanced: $\ge$ Expert (USACO Silver-USACO Platinum) **Teams of up to $4$** are allowed. You can find more information and register at: https://wwppc.tech/contest Join our Discord for in-contest communication and up...

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TopCoder SRM 629 — Long time with no SRMs Tomorrow, SRM 629 will be held at [11:00 EDT](http://www.timeanddate.com/worldclock/fixedtime.html?&day=12&month=08&year=2014&hour=11&min=00&sec=0&p1=179). This SRM is 3 weeks after the previous one (SRM 628 was on Jul 22, my birthday :D ). 3 weeks without TopCoder (except TCO14 Round 3), I'm sure that many people and I miss TopCoder too much! A sad fact that the number of SRMs is decreasing recently. After some months with 4 SRMs each, July has only 2, August has 3, and it's still not sure about next months. I don't know the reason, but it will be a great pity if there aren't any more SRMs. I like some SRM rules. The one I like most is that the ratings will change if we open a problem. This forces us to try our best to solve problems, or our ratings will decrease much (we can't keep our ratings unchange by not making any submissions). The next one is value of a problem starts decreasing when we open it (not from the beginning of the contests). We don't have to choose which problem ...

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Topcoder Open 2017 — Round 1A Topcoder Open is back! The first round will be 1A: Time: [12:00 noon EDT Saturday, April 1, 2017](https://www.timeanddate.com/worldclock/fixedtime.html?msg=TCO17+Round+1A&iso=20170401T12&p1=179) As usual top 250 active coder will advance to Round 2 directly. We will announce the list of coder a bit later, at this time you can check this blog: https://www.topcoder.com/blog/next-algorithm-track-automatic-berths/ You can find rules this year with the schedule here: https://tco17.topcoder.com/algorithm/rules/ Update: Byes are announced here (cut-off rating is 1783): https://tco17.topcoder.com/algorithm/byes/

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WWPIT 2024 Students at West Windsor-Plainsboro High School South (and North) are excited to present **WWPIT 2024**! WWPIT will be held online from 10:15 AM &mdash; 5:30 PM (EST) on [Sunday, June 2](https://www.timeanddate.com/worldclock/fixedtime.html?iso=20240602T1030&p1=179)! There will be **3** separately-timed rounds of **60-70** minutes for each division. Teams up of to **4** people are allowed. Registrations are now open at https://wwppc.tech/contest and will remain open until the day of the contest. **Divisions:**<br> The novice division will feature problems from AP CSA-USACO Silver level.<br> The advanced division will feature problems from USACO Silver-USACO Platinum level. **Credits:**<br> Problems were written by [user:cutsandstone,2024-05-22], [user:passwordisa,2024-05-22], [user:susvant,2024-05-22], and [user:spuh,2024-05-22]. <br>Thank you to our problem testers: [user:williamy125,2024-05-22], [user:kondasujay2,2024-05-22], [user:amaheria,2024-05-22], and [user:vikr...

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Topcoder Open 2017 — Round 1B Exactly 1 week after Round 1A, we will have our 2nd TCO round. Time: [12:00 noon EDT Saturday, April 8, 2017](https://www.timeanddate.com/worldclock/fixedtime.html?msg=TCO2017+Round+1B&iso=20170408T12&p1=179) You need to get top 750 with a positive score to advance. Note that if you have already advanced (in 1A or receive a bye), then you can't participate. Find rules this year with the schedule here: https://tco17.topcoder.com/algorithm/rules/

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Topcoder Open 2017 — Round 1C If you haven't advance to Round 2 yet &mdash; don't miss the last opportunity. Round 1C will start at [12:00 noon EDT Saturday, May 6, 2017](https://www.timeanddate.com/worldclock/fixedtime.html?msg=TCO2017+Round+1C&iso=20170506T12&p1=179) You need to get top 750 with a positive score to advance. Note that if you have already advanced (in 1A, 1B or received a bye), then you can't participate. Find rules this year with the schedule here: https://tco17.topcoder.com/algorithm/rules/

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Codeforces Global Rounds 2020: Current Results (GR7-GR10) In 2020 (as in 2019), with the support of XTX Markets, 6 rounds of the new Codeforces Global Rounds will be held. These will be common rounds for both divisions of 7–9 problems each. The duration of the rounds will be 2-3 hours, depending on the number and complexity of the problems. All such rounds will be rated for all participants. <i>At each such round, 50 brand T-shirts will be handed out, and we will be happy to give T-shirts to all problem authors and problem testers.</i> The prizes for the 6-round series in 2020: - In each round top-100 participants get points according to the [table](https://pastebin.com/QT5sXEaT). - 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. Current standings after four rounds (sorted by total points in four rounds): | Place | Contestant | = | GR 7 | GR 8 | GR 9 | GR 10| |--|--|--|--|--...

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SRM 692 Seeing as there's no blogpost from [user:chrome,2016-06-10] about the round a few hours before it... TC SRM 692 starts [soon](http://www.timeanddate.com/worldclock/fixedtime.html?&day=09&month=06&year=2016&hour=21&min=00&sec=0&p1=179). If you're up at night, you can participate! **UPD**: Contest over! As you may have noticed, I was the writer; it's worth it to read the problem of both divisions just for the stories. **Hints:** <spoiler summary="TreeSums"> <spoiler summary="hint 0"> The optimal node is either centroid. </spoiler> <spoiler summary="hint 1"> Centroids can be computed using something like LCA or a binary search. </spoiler> <spoiler summary="hint 2"> Think in terms of various sums over $2^k$ ancestors of each vertex, just like the jumps to the $2^k$-th ancestor used to compute LCAs. </spoiler> </spoiler> <spoiler summary="LinenCenter"> <spoiler summary="hint 1"> Solve the case $K=1$ first. </spoiler> <spoiler summary="hint 2"> Fast exponentiat...

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Hack me! (Codeforces Round #278 (Div. 1)) Waiting for next round, let's take some time and look at hacks in [contest:487]. That was really good round for hackers :) Previous posts (including post for Div. 2.) can be found [here](http://codeforces.me/search?query=hackme). [cut] <h3>Stats</h3> Yeah, everyone saw that there were plenty of hacks for problem A. How many exactly? Problem | <small>Successful hacks</small> | <small>Unsuccessful hacks</small> | Other* | Sum | <small>Solutions which can be hacked</small> | <small>Accepted solutions</small> | <small> All solutions on final tests</small>| :---:|:---:|:---:|:---:|:---:|:---:| <small> [problem:487A] </small> | <strong>460 (80.70%)</strong> | 96 (16.84%)| 14 (2.46%) | 570 | 58 (11.09%) | 465 (88.91%) | 523 | <small> [problem:487B] </small> | 8 (42.11%) | 8 (42.11%)| 3 (15.79%) | 19 | 99 (27.58%) | 260 (72.42%) | 359 | <small> [problem:487C] </small> | 67 (90.54%) | 5 (6.76%)| 2 (2.70%) | 74 | 45 (28.66%) | 112 (71.34%) | 157 | <small> [problem:487D] </sm...

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Useless CP Information #8: Are LGMs Overrated? Alright, clickbait title aside, how do tourist and jiangly get to 4000 rating? In chess, real life ratings cap out at around 2900, and even on online sites like Lichess, [the highest bullet players are 3300-3400, and just around 3000 for the other modes](https://lichess.org/player). Also, anecdotally, if rating is correct, the model predicts that someone who is 2940 should beat me 99.1% of the time. I have a gut feeling I beat more than 0.9% of GMs and LGMs in round 1105 and round 1108. <spoiler summary="Review on rating models if you forgot"> Rating represents win probability. In a match, for every 400 points player A is rated higher than player B, player A is 10 times more likely to win (exponentially). - If player A is rated 400 points higher than player B, then out of 11 games, player A should win 10 and player B should win 1. - If player A is rated 800 points higher than player B, then out of 101 games, player A should win 100 and player B should win 1. This can be ...

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TC SRM 638 The [last blog](http://codeforces.me/blog/entry/14530) got downvote <small>bombed <small>into</small> <small>oblivion</small></small>, but I have enough contribution to spare. TC SRM 638 takes place [soon (ಠ_ಠ)](http://www.timeanddate.com/worldclock/fixedtime.html?&day=02&month=11&year=2014&hour=21&min=00&sec=0&p1=179). Feel free to discuss the problems here after the round ends (because TC apparently doesn't have placeholders for new matches in its forum anymore...).

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arvindr9 Stream 13 Hello, Codeforces! I will stream myself doing a virtual contest of [Codeforces Round 1050 (Div. 4)](https://codeforces.me/contest/2148). The stream will be on [Thursday Sept 18 at 11am Eastern Time](https://www.timeanddate.com/worldclock/fixedtime.html?msg=arvindr9+Stream+13&iso=20250918T11&p1=179&ah=2). You can watch the stream in [my Twitch channel](https://www.twitch.tv/arvindr9). See you then!

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arvindr9 Stream 3 Hi everyone! I will be streaming myself upsolving [Educational Codeforces Round 115](https://codeforces.me/contest/1598) on Tuesday [10/19 from 6:30 &mdash; 8:30 AM EST](https://www.timeanddate.com/worldclock/fixedtime.html?msg=arvindr9+stream+3&iso=20211019T0630&p1=179&ah=2) at [my Twitch page](https://www.twitch.tv/arvindr9). I had 64 unique viewers (and a max of 7 simultaneous users) my last stream, which was fantastic! Seems like I figured out how to configure the video and audio settings during my last stream, so hopefully things should run more smoothly this time. This will be recorded (I also have the recording of stream 2, and will make that accessible soon). See you then!

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Topcoder SRM 698 Hi there, Topcoder SRM 698 will start in about 9 hours ([Sept 17, 12:00 noon EDT](http://www.timeanddate.com/worldclock/fixedtime.html?&day=17&month=09&year=2016&hour=12&min=00&sec=0&p1=179)). This round is Sponsored by Google, find more details [here](https://community.topcoder.com/tc?module=MatchDetails&rd=16802). Thanks for participating! The Div1-Medium and Hard were prepared to be used in TCO Round 3B, but [user:shangjingbo,2016-09-17] told me they are too easy (he got the idea for each of them in 10 minutes). It turns out they are not that easy. :P

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Topcoder SRM 500 Please note due to Daylight Savings, TopCoder time has changed to Eastern Daylight Time or UTC -4.<br> <br> TopCoder(R) Single Round Match <span class="il">500</span> is scheduled for Saturday, March 19, 2011 at 12:00 UTC -4 hours. &nbsp;In recognition of this milestone, TopCoder will be awarding 5,000 in cash prizes plus more! So get ready for the most prestigious TopCoder <span class="il">SRM</span> in years and give yourself a chance at becoming part of history!<br> <br> <span class="il">SRM</span> <span class="il">500</span> will begin at 12:00 UTC-4 with registration opening 3 hours prior to match time. Registration will be limited to 2,100 slots on a first come first serve basis so be sure to register early!<br> <br> Please be sure to check here for the start time in your time zone:<br> <a href="http://www.timeanddate.com/worldclock/fixedtime.html?&amp;day=19&amp;month=03&amp;year=2011&amp;hour=12&amp;min=00&amp;sec=0&amp;p1=179" target="_blank">http://www.time...

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A lightning Marathon before TCO16 NYC regional event If you like Marathons but don't have two weeks to dedicate to participation in a typical match, consider taking a look at the match that will run for 28 hours right before the TCO16 NYC regional event. The coding phase will start on Thursday, June 16 at 8:00 a.m. EDT (<a href="https://www.timeanddate.com/worldclock/fixedtime.html?msg=NYC+regional+event+Marathon&amp;iso=20160616T08&amp;p1=179">in your time zone</a>) and end on Friday, June 17 at Noon EDT (<a href="https://www.timeanddate.com/worldclock/fixedtime.html?msg=NYC+regional+event+Marathon+end&amp;iso=20160617T12&amp;p1=179">in your time zone</a>). It will be a rated event featuring a somewhat easier than usual problem (I am the writer ;-)) and following the usual Marathon rules (apart from the shorter duration). And if you happen to live in New York area, consider not only participating in the Marathon but stopping by at the <a href="https://tco16.topcoder.com/regional-events/nyc-usa/">TCO16 NYC regional event</a> at the Go...

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Codeforces Round #179 (Div. 2) This contest is a little hard for me. Only A and C were solved finally though I spent more than one hour on the other problems. My rank is 213. Here is the summary: Pro A: There are n elements in an array.If we can obtain an array where any two neighboring elements would be distinct in a finite time,print "YES" and print "NO" otherwise. This problem is not hard.What we should do is just counting the amount of each elements and find the max amount k.If k-1 is bigger than n-k,then print "NO" and print "YES" otherwise. Pro C: The first line tells us three integers n, m, k(1<=n,m,k<=10^5). The second line is an array(f) of n elements. Next m lines contain operations with three integers li, ri, di(1<=li<=ri<=n,0<=di<=10^5) which means to increase all array elements with numbers li,li+1,...,ri by value di. Next k lines contain queries with two integers x, y(1<=xi<=yi<=m) which means that one should apply operations with numbers xi,xi+1,..., yi to the array. After underst...

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Codeforces Round #179 tutorial Translated In English 296A &mdash; Yaroslav and Permutations Note that after applying the operations of the exchange, we can get any permutation of numbers. Not difficult to understand that the answer is "YES", if you can place a single number that it would not stand in the neighboring cells. Thus, if a some number is meeted C times, it must fulfill the condition C <= (n +1) / 2. 296B &mdash; Yaroslav and Two Strings We solve the inverse problem: count the number of ways to make comparable pair. To start count the number of ways to make the first line of less than equal to the second. This number equals the number of ways to do this for each item individually as they are position independent. Let's count the same amount, but when the second line-less equal to the first. And similarly to count the number of ways to make two lines equal. For each character values ​​can be considered as a simple cycle. Now we take the value of 10 to the number of question marks in the input file and subtract the answer...

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TopCoder Single Round Match 504.5 <p><span class="Apple-style-span" style="border-collapse: collapse; font-family: arial, sans-serif; font-size: 13px; "><b>TopCoder(R) Single Round Match 504.5</b> is scheduled for Tuesday, May 17, 2011 at 11:00 UTC -4 hours.</span><span class="Apple-style-span" style="border-collapse: collapse; font-family: arial, sans-serif; font-size: 13px; "><br></span><span class="Apple-style-span" style="border-collapse: collapse; font-family: arial, sans-serif; font-size: 13px; "><br></span><span class="Apple-style-span" style="border-collapse: collapse; font-family: arial, sans-serif; font-size: 13px; ">Please be sure to check here for the start time in your time zone:</span><span class="Apple-style-span" style="border-collapse: collapse; font-family: arial, sans-serif; font-size: 13px; "><br></span><span class="Apple-style-span" style="border-collapse: collapse; font-family: arial, sans-serif; font-size: 13px; "><a href="http://www.timeanddate.com/worldclock/fixedtime.html?iso=20110517T11&amp;p...

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TopCoder Open Round #3A Сегодня в [20:00](http://www.timeanddate.com/worldclock/fixedtime.html?iso=20120623T12&p1=179) по Москве 12 счастливчиков завоюют места в Parallel Round 3B Всем удачи!

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Topcoder SRM 747 and Editorials **Topcoder SRM 747** is scheduled to start at [11:00 UTC -5, Jan 19, 2018](https://www.timeanddate.com/worldclock/fixedtime.html?&day=19&month=01&year=2019&hour=11&min=00&sec=0&p1=179). Registration is now open for the SRM in the Web Arena or Applet and will close 5 minutes before the match begins **Editorials**: [https://www.topcoder.com/blog/single-round-match-747-editorials/](https://www.topcoder.com/blog/single-round-match-747-editorials/) - **Problem Writer**: [misof](http://www.topcoder.com/members/misof) CF:[user:misof,2019-01-15] - **Tester**: [Blue.Mary](topcoder.com/members/Blue.Mary) CF:[user:lucyanna2018,2019-01-19] _This is the fifth SRM of Stage 2 of TCO19 Algorithm._ **[Stage 2 TCO19 Points Leaderboard](https://tco19.topcoder.com/home/algorithm/algorithm-leaderboard)** | **[Topcoder Java Applet](http://www.topcoder.com/contest/arena/ContestAppletProd7.2.jnlp)** | [**Next SRM 748 &mdash; January 26**](https://calendar.google.com/event?action=TEMPLATE&tmeid=M...

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Topcoder Open 2017 — Round 2A TCO Round 2A will start at [12:00 noon EDT Saturday, May 20, 2017](https://www.timeanddate.com/worldclock/fixedtime.html?msg=TCO2017+Round+2A&iso=20170520T12&p1=179) Top 40 will advance to Round 3 and will get a T-shirt. Find more details here: https://tco17.topcoder.com/algorithm/rules/

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TC SRM 638 takes place [soon (ಠ_ಠ)](http://www.timeanddate.com/worldclock/fixedtime.html?&day=02&month=11&year=2014&hour=21&min=00&sec=0&p1=179). Feel free to discuss the problems here after the round ends (because TC apparently doesn't have placeholders for new matches in its forum anymore...). UPD: this blog post is now obsolete, because it doesn't show on the Recent actions list due to negative votes. Comment in [here](http://codeforces.me/blog/entry/14552) instead.

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Topcoder SRM 645 Topcoder SRM 645 will be held tomorrow (Monday) at 11:00 AM EST (see below for your time zone). [Official announcement here.](http://community.topcoder.com/tc?module=MatchDetails&rd=16277) So, see [here](http://www.timeanddate.com/worldclock/fixedtime.html?&day=12&month=01&year=2015&hour=11&min=00&sec=0&p1=179) for the time of Monday's round. This thread can be used for pre/post-contest discussion.

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Topcoder SRM 751 and Editorials Hi! **Topcoder SRM 751** is scheduled to start at [21:00 UTC -5, Feb 21, 2018](https://www.timeanddate.com/worldclock/fixedtime.html?&day=21&month=02&year=2019&hour=21&min=00&sec=0&p1=179). Registration is now open for the SRM in the Web Arena or Applet and will close 5 minutes before the match begins. **Problem Setter**: [majk](http://www.topcoder.com/members/majk) -- [user:majk,2019-02-21] **Editorials**: [https://www.topcoder.com/blog/single-round-match-751-editorials/](https://www.topcoder.com/blog/single-round-match-751-editorials/) _This is the third SRM of Stage 3 of TCO19 Algorithm. This stage will also help you qualify and win reimbursements/tickets to TCO19 Regional Events_. **[Stage 3 TCO19 Points Leaderboard](https://tco19.topcoder.com/home/algorithm/algorithm-leaderboard)** | **[Topcoder Java Applet](http://www.topcoder.com/contest/arena/ContestAppletProd7.2.jnlp)** | [**Next SRM 752 &mdash; March 6**](https://calendar.google.com/event?action=TEMPLATE&tmei...

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Topcoder SRM 750 and Editorials Hi! **Topcoder SRM 750** is scheduled to start at [11:00 UTC -5, Feb 8, 2018](http://www.timeanddate.com/worldclock/fixedtime.html?&day=08&month=02&year=2019&hour=11&min=00&sec=0&p1=179). Registration is now open for the SRM in the Web Arena or Applet and will close 5 minutes before the match begins. **Editorials**: [https://www.topcoder.com/blog/single-round-match-750-editorials/](https://www.topcoder.com/blog/single-round-match-750-editorials/) **Problem Setter**: [misof](http://www.topcoder.com/members/misof) SRM 750 will award you **double the TCO19 points** you would [generally receive](https://tco19.topcoder.com/home/algorithm/algorithm-rules). _This is the second SRM of Stage 3 of TCO19 Algorithm. This stage will also help you qualify and win reimbursements/tickets to TCO19 Regional Events_. **[Stage 3 TCO19 Points Leaderboard](https://tco19.topcoder.com/home/algorithm/algorithm-leaderboard)** | **[Topcoder Java Applet](http://www.topcoder.com/contest/arena/Co...

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Topcoder Single Round Match 661 I usually like to wait for [user:chrome,2015-06-11] or someone else to remind all you good folk about an upcoming SRM but it seems like they have forgotten. So here goes. Hi there! Tomorrow at [6:30 IST](http://www.timeanddate.com/worldclock/fixedtime.html?&day=11&month=06&year=2015&hour=21&min=00&sec=0&p1=179) will be held [Topcoder SRM 661](http://community.topcoder.com/tc?module=MatchDetails&rd=16464). Let's discuss problems after contest! GL && HF.

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TCO12 Algorithm Qualification Round 1B The second qualification round will be held today at [20:00 (Moscow time)](http://www.timeanddate.com/worldclock/fixedtime.html?iso=20120407T12&p1=179). You should be registered at TCO 2012 to participate in this round. Number of participant is limited to the first 2000 competitors. Programmers from both divisions will compete together. Register, psrticipate, win! =) Third qualification round will be held a week later, 14 april at the same time.

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Topcoder SRM #607 Round starts in [10 minutes](http://www.timeanddate.com/worldclock/fixedtime.html?&day=03&month=02&year=2014&hour=07&min=00&sec=0&p1=179).

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TopCoder Open Round #4 <p><span class="Apple-style-span" style="font-family: verdana, arial, sans-serif; font-size: 12px; line-height: 20px; ">Добрый день.</span></p><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; font-family: verdana, arial, sans-serif; font-size: 12px; line-height: 20px; ">Сегодня в&nbsp;<a href="http://timeanddate.com/worldclock/fixedtime.html?month=7&amp;day=23&amp;year=2011&amp;hour=12&amp;min=0&amp;sec=0&amp;p1=179" style="color: rgb(0, 0, 204); ">20:00 по Москве</a>&nbsp;состоится четвертый отборочный раунд TopCoder Open. В пятый раунд пройдет 60 участников. Всем удачи!</div>

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SRM 600.5 Special Round Match On this [Sunday](http://www.timeanddate.com/worldclock/fixedtime.html?&day=15&month=12&year=2013&hour=12&min=00&sec=0&p1=179) will take place Topcoder SRM 600.5 <br>It's a Special Round Match **40 t-shirts and $600 in prizes 10 t-shirts to spectators** <br>So this month we have **5** SRMs :) <br>don't miss it <br>Goodluck **UPD1:** for more information [Click here](http://www.topcoder.com/news/2013/12/11/celebrate-srm-600-with-us-two-matches-200-t-shirts-and-money-prizes/)

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TopCoder Open Round #2 <p><span class="Apple-style-span" style="font-family: verdana, arial, sans-serif; font-size: 12px; line-height: 20px; ">Добрый день.</span></p><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; font-family: verdana, arial, sans-serif; font-size: 12px; line-height: 20px; ">Сегодня в&nbsp;<a href="http://timeanddate.com/worldclock/fixedtime.html?month=6&amp;day=25&amp;year=2011&amp;hour=12&amp;min=0&amp;sec=0&amp;p1=179" style="color: rgb(0, 0, 204); ">20:00 по Москве</a>&nbsp;состоится второй отборочный раунд TopCoder Open. В третий раунд пройдет 350 участников. Всем удачи!</div><p></p>

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Codeforces Beta Round #3 - Thousand apologies <p> It seems everyone is in the know that Codeforces Beta Round#3 didn’t take place in the appointed time. Seemingly, it happened because of the increased popularity of the site, on the one hand, and some of our bugs, on the other. For sure, it’s a pity that things went in such a way. On the other part, if everything had failed during the contest, it would have been worse. The contest is rescheduled for <b><u>Sunday, 15:00 (Moscow time)</u></b>. Please be sure to check here for the start time in your time zone: <a href="http://www.timeanddate.com/worldclock/fixedtime.html?&amp;day=07&amp;month=03&amp;year=2010&amp;hour=07&amp;min=00&amp;sec=0&amp;p1=179">http://www.timeanddate.com/worldclock/fixedtime.html?&amp;day=07&amp;month=03&amp;year=2010&amp;hour=07&amp;min=00&amp;sec=0&amp;p1=179</a></p><p> I’d like to remind you that the project is in Beta yet, and we’ll work on the problem and try to fix it. </p><p> Thanks for your understanding,<br> MikeMirzayanov </p>

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TopCoder Open Round #1 <p>Good afternoon.</p><div>TopCoder Open Online Round #1 will be conducted today at&nbsp;<a href="http://timeanddate.com/worldclock/fixedtime.html?month=6&amp;day=18&amp;year=2011&amp;hour=12&amp;min=0&amp;sec=0&amp;p1=179">12:00 ET</a>. Top 850 participants will advance to the second round. Good luck!</div><p></p>

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Topcoder SRM 559 Topcoder SRM 559 is going to be held on Tuesday , 30th October 2012 at 21:00 EDT ([your timezone](http://www.timeanddate.com/worldclock/fixedtime.html?&day=30&month=10&year=2012&hour=21&min=00&sec=0&p1=179)) The registration starts 3 hours prior to the match in the arena and is restricted to the first 2500 contestants . You can discuss about the SRM here once it is over.(and also on the topcoder forum [here](http://apps.topcoder.com/forums/?module=ThreadList&forumID=560474)). Also , there is going to be a test round 2 from 2 hours from now in the arena ([your timezone](http://www.timeanddate.com/worldclock/fixedtime.html?&day=30&month=10&year=2012&hour=16&min=05&sec=0&p1=179))

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The Journey to Candidate Master: Plateaus, Faith, and Consistency I started **Competitive programming** in **August 2024**, at the beginning of my second year of college. My first few Div.2 contests were humbling — I could solve 1 problem, sometimes 2. In Div.3, solving 3 problems felt like a win. But what kept me going was not the rating, but the nature of the problems themselves. At the **800–1000 level**, it’s mostly about thinking — no fancy algorithms, no heavy data structures — just logic and clarity. **That fascinated me**, and I decided to stay. **---------------------------------------------------------------------------------------------------------------------------------------------------** The Phase Nobody Talks About ---------------------------- In the first four months, I climbed quickly and reached **1459** on **12 January 2025.** Then the graph stopped moving. For the next **110 Days**, I was **stuck below 1450**. I practiced. I gave contests. I did everything I had been doing before. But nothing showed. On...

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Blog collection <p>________________________________________________________________________________________<br><br></p><h3><b>Puzzle</b></h3><ul><li><a href="http://codeforces.me/blog/entry/66">Red and Black hair</a>, </li><li><a href="http://codeforces.me/blog/entry/112">The 12 chairs and diamonds</a></li><li><a href="http://codeforces.me/blog/entry/228">Monty Hall Problem</a></li></ul><br><br><h3>Useful <br></h3><ul><li><a href="http://codeforces.me/blog/entry/70">Petr Mitrichev, 3 days in Sao Paulo Training Camp 2010</a></li><li><a href="http://codeforces.me/blog/entry/512">Useful links</a></li><li><a href="http://codeforces.me/blog/entry/529">Problem Set Analysis Of CodeForces</a></li><li><a href="http://codeforces.me/blog/entry/546">Discussions Of CodeForces Round</a></li><li><a href="http://codeforces.me/blog/entry/1492">ALL CodeForces rounds Tutorial</a></li><li><a href="http://codeforces.me/blog/entry/1534">Online Judge Locator</a></li><li><a href="http://codeforces.me/blog/entry/170...

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Topcoder SRM 733 Topcoder SRM 733 is scheduled to start at [12:00 UTC -4, April 14, 2018](https://www.timeanddate.com/worldclock/fixedtime.html?msg=Topcoder+SRM+733&iso=20180414T12&p1=179&ah=2). Featured Problem Writer: [ltdtl](http://www.topcoder.com/members/ltdtl) Update: Match Editorials: https://www.topcoder.com/blog/single-round-match-733-editorials/ SRM 733 will give you a chance to move up the ranks to get an automatic qualification to Round 2 of [TCO18 Algorithm Track](https://www.topcoder.com/blog/upcoming-tco18-algorithm-competition/). You will be able to register for the SRM in the Arena or Applet 4 hours prior to the start of the match. Registration closes 5 minutes before the match begins, so make sure that you are all ready to go. Don’t know how to compete in Topcoder SRMs? Check out [this](https://www.topcoder.com/member-onboarding/competing-in-an-algorithm-match-srm/) guide to know how to compete in an SRM. You can compete using: - Topcoder Web Arena(Beta) — Please...

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Topcoder Single Round Match 686 Всем привет! Завтра в [04:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=28&month=03&year=2016&hour=21&min=00&sec=0&p1=179) состоится [Topcoder SRM 686](https://community.topcoder.com/tc?module=MatchDetails&rd=16690). Предлагаю обсудить задачи после контеста.

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arvindr9 Stream 14 Hello Codeforces! I'll stream myself this Thursday, doing a virtual of Codeforces Round 1065 (Div 3). The stream will be on [Thursday Nov 20 at 3pm Eastern time](https://www.timeanddate.com/worldclock/fixedtime.html?msg=arvindr9+Stream+14&iso=20251130T15&p1=179). You can watch the stream in my [Twitch channel](https://www.twitch.tv/arvindr9). See you then!

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Topcoder Single Round Match 685 Всем привет! Сегодня в [19:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=19&month=03&year=2016&hour=12&min=00&sec=0&p1=179) состоится [Topcoder SRM 685](https://community.topcoder.com/tc?module=MatchDetails&rd=16689). Приглашаю всех к участию и предлагаю обсудить задачи здесь после контеста.

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Codeforces Popularity Ranking Hello Codeforces! There has been several blogs similar to this. I know about [TOP 15 most popular users on codeforces](http://codeforces.me/blog/entry/49122) and [Who is the most popular?](http://codeforces.me/blog/entry/21041). But as none of these are updated, I thought this might be helpful. I have just calculated the most popular handles in Codeforces. I only considered those handles which have at least one rated contest. Begging my pardon to them who hasn't participated in any rated round. And here, the popularity depends simply on the number of people you are friend of. The complete standings can be found [here](https://docs.google.com/spreadsheets/d/1ADlF-bd6pBYCap75yzf-pUnVwI9f9YmPkiYNW3lD-xo/edit?usp=sharing)(This may took a while to load at the bottom). Anyway here is Top 200 handles. | Rank | Handle | Follower | |---|---|---| 1. | [user:tourist,2018-08-22] | 14082 | 2. | [user:Petr,2018-08-22] | 6430 | 3. | [user:OO0OOO00O0OOO0O00OOO0OO,2018-08-22] | 420...

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TopCoder Single Round Match 560 Hi friends, <a href="http://community.topcoder.com/tc?module=MatchDetails&rd=15182">TopCoder Single Round Match 560</a> will be at <a href="http://www.timeanddate.com/worldclock/fixedtime.html?&day=10&month=11&year=2012&hour=12&min=10&sec=0&p1=179">12:10 PM EST</a>. Have a great contest. You can also read <a href="http://codeforces.me/blog/entry/5809">this blog</a>, it will be a great contest in Latin American.

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Single Round Match 527 <p>Сегодня в <a href="http://www.timeanddate.com/worldclock/fixedtime.html?&amp;day=17&amp;month=12&amp;year=2011&amp;hour=12&amp;min=00&amp;sec=0&amp;p1=179">21:00 MSD</a> состоится <a href="http://community.topcoder.com/tc?module=MatchDetails&amp;rd=14552">Single Round Match 527</a>. Так как темы до сих пор почему-то не было, я решил создать.</p>

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My contest got unrated, but I registered as individual participant. Why? [SOLVED] Hi [user:MikeMirzayanov,2025-06-04] [user:FelixArg,2025-06-04] I registered as Individual Participant on Tuesday, June 3, 2025 for Educational Codeforces Round 179 (Rated for Div. 2), half an hour before. I solved 2 problems. My ranking is being shown in the Standings tab (Image Attached). But my contest is being unrated (Image Attached). I registered as Unrated in the previous contest Codeforces Round 1028 (Div. 2). But not on this one. Kindly look into this? or is this expected? Thank you IMAGE LINKS FYI: https://ibb.co/DgYJCW3J https://ibb.co/DgL4NM0s

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Topcoder Single Round Match 687 Всем привет! Завтра в [14:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=07&month=04&year=2016&hour=07&min=00&sec=0&p1=179) состоится [Topcoder SRM 687](https://community.topcoder.com/tc?module=MatchDetails&rd=16708). Приглашаю всех поучаствовать и предлагаю обсудить задачи после контеста.

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Single Round Match 633 Today will be held [Single Round Match 633](http://community.topcoder.com/tc?module=MatchDetails&rd=16076) at [19:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=17&month=09&year=2014&hour=11&min=00&sec=0&p1=179). Let's discuss here problems after the contest. **UPD: Contest delayed to 15 minutes**

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TopCoder Single Round Match 552 (SRM 552) Hi, --- Remember that tomorrow will be this round in TopCoder. Here you have the link: http://community.topcoder.com/tc?module=MatchDetails&rd=15174. Registration will start at 06:00 PM EDT and the contest will be at 09:00 PM EDT. You can check the time for your country here: http://www.timeanddate.com/worldclock/fixedtime.html?&day=16&month=08&year=2012&hour=21&min=00&sec=0&p1=179. See you there and have a great contest.

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Topcoder Single Round Match 688 Всем привет! Завтра в [18:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=15&month=04&year=2016&hour=11&min=00&sec=0&p1=179) состоится [Topcoder SRM 688](https://community.topcoder.com/tc?module=MatchDetails&rd=16709). Предлагаю обсудить задачи здесь после контеста!

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TopCoder Single Round Match 526.5 <p>Что-то мне не пришло письмо о том, что скоро будет СРМ, уже через 5.5 часов он состоится в 6:00 по московскому времени. <a href="http://www.timeanddate.com/worldclock/fixedtime.html?&amp;day=23&amp;month=12&amp;year=2011&amp;hour=21&amp;min=00&amp;sec=0&amp;p1=179">Тут</a> можно уточнить время начала в других часовых поясах.</p><p>Предлагаю как всегда обсудить здесь задачи по окончании тура.</p><p>по информации <a href="http://snarknews.info/">snarknews.info</a></p><p><strong>Анонс: 24.12.2011 (сб), 06:00</strong> на сайте <strong>www.topcoder.com</strong> состоится Single Round Match 526.5, назначенный в качестве &quot;компенсационного&quot; из-за проблем с регистрацией перед началом SRM 526.</p><p><strong>UPD: Я ошибся на 24 часа,  матч будет только через сутки.</strong> П<strong>рошу прощения, </strong><strong>заработался.</strong></p>

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Invitation for TopCoder Single Round Match (SRM) 551 Hi everybody: ------------- Remember that tomorrow will be this round in TopCoder. Here you have the link: http://community.topcoder.com/tc?module=MatchDetails&rd=15173 and registration will start at 09:00 AM EDT and the contest will start at 12:10 PM EDT. You can check the time for your country here: http://www.timeanddate.com/worldclock/fixedtime.html?&day=04&month=08&year=2012&hour=12&min=10&sec=0&p1=179. Have a nice contest!!!!

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Topcoder Single Round Match 690 Всем привет! Завтра в [04:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=03&month=05&year=2016&hour=21&min=00&sec=0&p1=179) состоится личное [соревнование](https://community.topcoder.com/tc?module=MatchDetails&rd=16729). Приглашаю всех поучаствовать и предлагаю обсудить задачи после контеста!

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Topcoder Single Round Match 677 Всем привет! **Сегодня** <s>Завтра</s> в [20:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=26&month=12&year=2015&hour=12&min=00&sec=0&p1=179) состоится [Topcoder SRM 677](https://community.topcoder.com/tc?module=MatchDetails&rd=16627). Предлагаю обсудить задачи здесь после контеста.

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Topcoder Single Round Match 680 Привет всем! <s>Завтра</s><b>Сегодня</b> в [19:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=28&month=01&year=2016&hour=11&min=00&sec=0&p1=179) состоится [Topcoder SRM 680](https://community.topcoder.com/tc?module=MatchDetails&rd=16650). Предлагаю обсудить задачи после контеста.

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TopCoder Single Round Match 533 Hello coders, next [TC SRM 533](http://community.topcoder.com/tc?module=MatchDetails&rd=14726) is scheduled on [02.18.2012 12:00 PM EST](http://www.timeanddate.com/worldclock/fixedtime.html?&day=18&month=02&year=2012&hour=12&min=00&sec=0&p1=179). It's brought by Google. Registration starts 3 hours before start and ends 5 minutes before start (be aware that even if coding phase starts at 12:05, **registration ends at 11:55**). Also there is limit for number of participants (something like 2300 or so), but typically there is not so many coders (just in time of TCO, number of participants in SRMs increases over the limit).

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Topcoder Single Round Match 684 Hi there! Tomorrow at [19:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=07&month=03&year=2016&hour=11&min=00&sec=0&p1=179), will be held [Topcoder SRM 684](https://community.topcoder.com/tc?module=MatchDetails&rd=16688). Let's discuss problems after contest.

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TopCoder Single Round Match 521 <p>Сегодня, в четверг, 13 октября 2011 года в 15:02 по Москве состоится 521-й TopCoder Single Round Match (<a href="http://www.timeanddate.com/worldclock/fixedtime.html?&amp;day=13&amp;month=10&amp;year=2011&amp;hour=07&amp;min=02&amp;sec=0&amp;p1=179">время в других городах</a>).<br /></p>

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CF #179 div1 screencast Here is a screencast of me solving this round: [youtube](http://www.youtube.com/watch?v=jWnPqmqcyFE) To watch comfortably (and see clear text), choose 1080p and watch full-screen on a 1920x1080 resolution or higher. Download link in 1680x1050: [link](http://dj3500.webfactional.com/screencasts/2013-04-11%20codeforces%20round%20179.mkv)

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Topcoder Single Round Match 672 Всем привет! Завтра в [04:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=20&month=10&year=2015&hour=21&min=00&sec=0&p1=179) утра состоится [Topcoder SRM 672](http://community.topcoder.com/tc?module=MatchDetails&rd=16552). Предлагаю обсудить задачи после контеста. **UPD:** [Editorial](http://www.codeforces.com/blog/entry/21112)

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Topcoder Single Round Match 655 Всем привет! Сегодня в [18:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=09&month=04&year=2015&hour=11&min=00&sec=0&p1=179) состоится [Topcoder SRM 655](http://community.topcoder.com/tc?module=MatchDetails&rd=16415). Предлагаю обсудить задачи после контеста.

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Topcoder Single Round Match 679 Привет всем! Завтра в [15:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=20&month=01&year=2016&hour=07&min=00&sec=0&p1=179) состоится [Topcoder SRM 679](https://community.topcoder.com/tc?module=MatchDetails&rd=16649). Предлагаю обсудить задачи после контеста. **Контест начинается менее чем за полтора часа, успейте зарегистрироваться!**

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Topcoder Single Round Match 673 Всем привет! Сегодня в [19:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=18&month=11&year=2015&hour=11&min=00&sec=0&p1=179) состоится [Topcoder SRM 673](https://community.topcoder.com/tc?module=MatchDetails&rd=16616). Предлагаю обсудить задачи после контеста.

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Topcoder Single Round Match 652 Всем привет! Завтра, в [18:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=09&month=03&year=2015&hour=11&min=00&sec=0&p1=179) состоится [SRM 652](http://community.topcoder.com/tc?module=MatchDetails&rd=16316). Предлагаю обсудить задачи после контеста!

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Topcoder Single Round Match 640 Всем привет! Сегодня в [20.00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=09&month=12&year=2014&hour=12&min=00&sec=0&p1=179) состоится [Topcoder SRM 640](http://community.topcoder.com/tc?module=MatchDetails&rd=16083). Давайте обсудим задачи после контеста

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TopCoder Member Single Round Match 478 4 августа в <a href="http://www.timeanddate.com/worldclock/fixedtime.html?month=8&amp;day=4&amp;year=2010&amp;hour=7&amp;min=0&amp;sec=0&amp;p1=179">15:00 MSD</a>&nbsp;состоится очередной TopCoder SRM

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Mail.Ru Cup 2018 — Results of R1+R2+R3 Here are merged results of [contest:1054], [contest:1055] and [contest:1056] according to the GP100 scores (see the announcement for the details https://codeforces.me/blog/entry/62355). Best two contests give the summary score of a participant. This table is unofficial yet. But anyway... congratulations to the winnerzzzz! | Place | Contestant | = | Round 1 | Round 2 | Round 3| | - | - | - | - | - |-| | 1 | [user:mnbvmar,2018-11-25] | 1497 | 1000 | 497 | 29 | | 2 | [user:V--o_o--V,2018-11-25] | 1281 | 575 | 575 | 706 | | 3 | [user:Radewoosh,2018-11-25] | 1265 | &mdash; | 265 | 1000 | | 4 | [user:aid,2018-11-25] | 1204 | 204 | 1000 | 142 | | 5 | [user:LHiC,2018-11-25] | 1203 | 497 | 706 | 226 | | 6 | [user:Um_nik,2018-11-25] | 997 | 706 | 291 | 235 | | 7 | [user:ksun48,2018-11-25] | 788 | 291 | &mdash; | 497 | | 8 | [user:SpyCheese,2018-11-25] | 742 | 371 | 371 | 265 | | 9 | [user:RAVEman,2018-11-25] | 619 | 19 | 176 | 443 | | 10 | [user:scott_wu,2018-11-25] | 614...

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Topcoder Single Round Match 646 Hi %username%! Tomorrow at [05:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=15&month=01&year=2015&hour=21&min=00&sec=0&p1=179) will be held [Topcoder SRM 646](http://community.topcoder.com/tc?module=MatchDetails&rd=16278) Let's discuss problems after contest GL && HF

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Single Round Match 611 Через два часа ([16:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=04&month=03&year=2014&hour=07&min=00&sec=0&p1=179)) состоится Single Round Match 611. Не пропустите, и желаю удачи!

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Single Round Match 530 Опять таки, удивившись что темы до сих пор нет решил создать.<div><br /></div><div>Завтра(а скоро уже сегодня), 20 января 2012 года в <a href="http://www.timeanddate.com/worldclock/fixedtime.html?&amp;day=19&amp;month=01&amp;year=2012&amp;hour=21&amp;min=00&amp;sec=0&amp;p1=179">6:00 MSD</a> пройдет <a href="http://community.topcoder.com/tc?module=MatchDetails&amp;rd=14723">SRM530</a>.</div>

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Topcoder Single Round Match 532 <p>Копись вкладик.</p><p>Соревнование начнётся в <a href="http://www.timeanddate.com/worldclock/fixedtime.html?&day=09&month=02&year=2012&hour=11&min=00&sec=0&p1=179">9 февраля в 20:00 по саратовскому</a>.</p><p>Да пребудет с нами Сила!</p><p><img src="http://pics.livejournal.com/sharpc/pic/00089k6w" /></p> UPD. Артём крут!

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Topcoder Single Round Match 643 Всем привет! <s>Завтра</s> <b>Сегодня</b> в [20:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?&day=27&month=12&year=2014&hour=12&min=00&sec=0&p1=179) состоится [Topcoder SRM 643](http://community.topcoder.com/tc?module=MatchDetails&rd=16086) Предлагаю обсудить задачи после контеста!

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TopCoder Single Round Match 682 Hi there! After Tomorrow at [05:00 MSK](http://www.timeanddate.com/worldclock/fixedtime.html?msg=TopCoder+SRM+682&iso=20160222T21&p1=179), will be held [TopCoder SRM 682.](https://community.topcoder.com/tc?module=MatchDetails&rd=16652). [Registration](http://www.timeanddate.com/worldclock/fixedtime.html?msg=Registration+SRM+682&iso=20160223T01&p1=166) SRM 682. Let's discuss problems after contest.

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