Problem of cheating in Competitive Programming You are probably already familiar with the following cheating methods, submitting your solution on alt account, with 4o, and then deep seek, and then o1, and then o3, finding solutions on telegram, finding solutions on youtube, finding solutions on discord, asking your blue rated friend, asking your purple rated friend, asking your orange rated friend, asking your red rated friend, asking your lgm rated friend, play as a team of cyan, play as a team of blue, play as a team of purple, play as a team of orange, play as a team of red, play as a team of lgm, asking some other blue that is not your friend, asking some other purple that is not your friend, asking some other orange that is not your friend, asking some other red that is not your friend, asking some other Lgm that is not your friend, pay an orange to play the contest for you, pay a red to play the contest for you, pay an LGM to play the contest for you, print out katcl and bring it to IOI, print out cp-algorithm and bring it to...

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Does Codeforces need a moderation system? In the recent months, the number of trash blogs on Codeforces has risen. Thankfully, they are mostly being ignored, and are very often recognizable by their title and/or author handle, but they still show up in the Recent Actions, making navigation through actually meaningful and good content like tutorials/contest invitations/etc harder. And very often, it's the same person posting one useless blog after another, not getting banned even after five or six instances. Personally, I am sick of those blogs, and I don't think I'm the only one. I understand why they don't get banned. Mike, Gera Nazarov and other people responsible for the platform are very busy maintaining the testing system, catching cheaters, improving Polygon and doing other work which lets Codeforces continue running and improving. They don't have time for digging through everything that gets posted, and that's perfectly understandable. So, I think we need some other people who can do this. Maybe a crew of some uni...

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Congratulations to Sparky_Master_WCH1226 Dear [user:Sparky_Master_WCH1226,2022-04-19], Congratulations for reaching <span class="user-red">Grandmaster</span> and gaining your brand new <span class="user-red">red</span> name <span class="rated-user user-red">Sparky_Master_WCH1226</span>!!! We have been so used to seeing <span class="rated-user user-orange">Sparky_Master_WCH1226</span> ever since you became <span class="user-orange">Master</span> in [contest:1623], less than 24 hours after you reached <span class="user-violet">Candidate Master</span> in [contest:1622]. While red is a nice colour, it is quite sorrowful to say goodbye to the familiar <span class="rated-user user-orange">Sparky_Master_WCH1226</span>. Goodbye, goodbye, goodbye, we will remember <span class="rated-user user-orange">Sparky_Master_WCH1226</span> forever... Unless, of course, if it occurs that our beloved (or shall I say, much loathed?) <span class="rated-user user-red">Sparky_Master_WCH1226</span> decides to go back to the familiar <span clas...

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Casual Racism on Codeforces? Hi all. Recently I've been seeing a lot of weird blog posts and comments from/regarding this user [Sparky_Master_WCH1226](https://codeforces.me/profile/Sparky_Master_WCH1226). He claims to be from Botswana (I'm pretty sure he's not and just he's trolling). His behaviour and comments in weird/broken English perpetuate the racist/harmful stereotype that people from Africa are stupid and can't communicate properly. I don't know what Codeforces' policy is on this kind of behaviour. But as an African, seeing such behaviour makes me pretty uncomfortable. Especially when [other users](https://codeforces.me/blog/entry/102249) seem to be [jumping](https://codeforces.me/blog/entry/102200) on the bandwagon. Maybe I'm just being butthurt and he is just having a bit of harmless fun. What do you think?

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[Tutorial] Kruskal Reconstruction Tree Hello CodeForces! Instead of posting a not-so-meaningful blog that helps farm my contribution, today, I would like to have the CodeForces community being benefited at the same time. Therefore, I would like to make a blog about one of my favourite techniques applied on trees, the Kruskal Reconstruction Tree. Although this technique is not too commonly used in CodeForces rounds, it has become more and more popular in other competitions such as the IOI. Also, I found out that there are some very limited resources about this technique that is written in English. Therefore, I would like to write a blog on KRT. **If you find this blog useful, please DOWNVOTE this blog.** It will give me immense support to do other topics like these in the future. #Prerequisites: Finding MST by using Kruskal's Algorithm Disjoint Set Union Finding lowest common ancestor in $O(n log n)$ precomputation time and $O(log n)$ for each query. #Problem: Given a graph with $N$ nodes and $M$ weighte...

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Congratulations to the Winner of Meta Hacker Cup 2025! Congratulations to [user:Geothermal,2025-10-20] for winning Meta Hacker Cup 2025! On Saturday, 18 October, the final and only round of Meta Hacker Cup 2025 was held. Geothermal managed to AK the contest in 35 minutes and 35 seconds with a total penalty time of 1:28:26. Not only is an AK of the final round incredibly rare, but Geothermal also achieved it at record speed. I have heard that next year, submissions will continue to be clarification-based. They will also introduce a new rule not to release Round 1 results before Round 3 is concluded. I wonder how this would change the meta.

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[Unrelated] Brief Summary of “On the Six Fallen States” **Disclaimer: This is completely unrelated to competitive programming.** <br><br> In the light of the recent blog posted (and deleted) by sparky_master_wch1226 and qwaszx_ak_ioi, coincidently, the same classic Chinese article, “On the Six Fallen States” (六國論, 六国论) is mentioned. This article was written by Su Xan (蘇洵, 苏洵) during the Northern Song Dynasty (北宋), and it is now shared by users living in Botswana (probably not) and Japan on a competitive programming platform after almost a millennium. Undoubtedly, this is one of the best articles in the history of China. Indeed, in most Chinese-speaking places, this article is introduced to students. Not only does this article demonstrate high-level argumentation skills, but at the same time reflects the history of the warring states period (戰國時代, 战国时期) to the situation at that time and allows readers to learn from the past.<br><br> Starting with the first paragraph, <br><br> 六國破滅，非兵不利，戰不善，弊在賂秦。賂秦而力虧，破滅之道也。 或曰：「六國互喪，率賂秦耶？」曰：「不賂者以賂者喪。」蓋失強援...

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Thank you Sparky_Master_WCH1226 Thank you [user:Sparky_Master_WCH1226,2022-11-30] for inspiring to do CP, his journey through CP has been very inspiring to me and this sir is very inspiring. I can't help but feel inspired by his inspiration emanating from his godly aura of inspiration. He has been so inspiring for me and so many others that I am sure many others have been inspired by his inspiring acts. His coding journey is very inspiring and has inspired me to inspire others by talking about how he inspired me and now I'm inspired to inspire others because of his inspiring. [cut] I even drew a picture of him 

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Where is Sparky_Master_WCH1226? Why I didn't see him in codeforces community for about 10 days, did he be banned to post the blogs??why??

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A guy named Sparky_Master_WCH1226 [user:Sparky_Master_WCH1226,2022-03-22] why your blogs are meaningless and boring? y0ur5, sinc3r3ly, [user:20llmc,2022-03-22]

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Codeforces Round #eight hundred and fifty Komments Hereinafter assume div 1 notation is used. Problem ?1: insignificant Problem ?2: nonsense Problem @: silly Problem A: trivial Problem B: dumb Problem C: uninteresting Problem D: stupid Problem E: toxic Problem F: not read also bump when release editorial ###六国破灭非兵不利战不善弊在赂秦赂秦而力亏破灭之道也或曰六国互丧率赂秦耶曰不赂者以赂者丧盖失强援不能独完故曰弊在赂秦也秦以攻取之外小则获邑大则得城较秦之所得与战胜而得者其实百倍诸侯之所亡与战败而亡者其实亦百倍则秦之所大欲诸侯之所大患固不在战矣思厥先祖父暴霜露斩荆棘以有尺寸之地子孙视之不甚惜举以予人如弃草芥今日割五城明日割十城然后得一夕安寝起视四境而秦兵又至矣然则诸侯之地有限暴秦之欲无厌奉之弥繁侵之愈急故不战而强弱胜负已判矣至于颠覆理固宜然古人云以地事秦犹抱薪救火薪不尽火不灭此言得之齐人未尝赂秦终继五国迁灭何哉与嬴而不助五国也五国既丧齐亦不免矣燕赵之君始有远略能守其土义不赂秦是故燕虽小国而后亡斯用兵之效也至丹以荆卿为计始速祸焉赵尝五战于秦二败而三胜后秦击赵者再李牧连却之洎牧以谗诛邯郸为郡惜其用武而不终也且燕赵处秦革灭殆尽之际可谓智力孤危战败而亡诚不得已向使三国各爱其地齐人勿附于秦刺客不行良将犹在则胜负之数存亡之理当与秦相较或未易量呜呼以赂秦之地封天下之谋臣以事秦之心礼天下之奇才并力西向则吾恐秦人食之不得下咽也悲夫有如此之势而为秦人积威之所劫日削月割以趋于亡为国者无使为积威之所劫哉夫六国与秦皆诸侯其势弱于秦而犹有可以不赂而胜之之势苟以天下之大下而从六国破亡之故事是又在六国下矣

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Komments on codeTON round 5 problem D This trick is well known in China. ================================== For poor people that cannot use youtube: [https://www.bilibili.com/video/BV1uT4y1P7CX/](https://oi-wiki.org/graph/diff-constraints/) For international users: [https://www.youtube.com/watch?v=dQw4w9WgXcQ](https://oi-wiki.org/graph/diff-constraints/)

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Thank you, Sparky_Master_WCH1226 while there are so many thank you posts on cf, has anyone else wondered where is sparky master [user:Sparky_Master_WCH1226,2022-12-01] please come back sincerely, a lonely motswana

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