Online mirror of The 2024 ICPC Asia Jakarta Regional Contest Selamat pagi Codeforces! We're going to hold The 2024 ICPC Asia Jakarta Regional Contest. We invite you to join the online mirror contest [2024-2025 ICPC, Asia Jakarta Regional Contest (Online Mirror, Unrated, ICPC Rules, Teams Preferred)](https://mirror.codeforces.com/contests/2045) on Codeforces. It'll be held on [contest_time:2045] and will last for 5 hours. The mirror will be held using ICPC-style scoring with 10 to 13 problems. The problem statements will only be available in English. We encourage participating as a team using only one computer for coding (as in ICPC contests). The mirror will be unrated. Some useful links: * [The 2024 ICPC Asia Jakarta homepage](https://competition.binus.ac.id/icpc2024) * [The regional information in ICPC Global](https://icpc.global/regionals/finder/Jakarta) * [The onsite scoreboard](https://competition.binus.ac.id/contest) We hope that you'll enjoy the contest. Good luck and have fun! **UPD.** The mirror has ended! You can find...

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ICPC should NOT be done online I have been thinking about this for more than a year. I think it's time to share my thoughts. **Disclaimer: all opinions written in this post are purely personal and not tied with any affiliation/institution I am working with.** The [global pandemic we are encountering](https://en.wikipedia.org/wiki/COVID-19_pandemic) has affected many aspects of our life. While we need to adapt to doing most of our activities online, competing in the [International Collegiate Programming Contest (ICPC)](https://en.wikipedia.org/wiki/International_Collegiate_Programming_Contest) -- or similar high-stakes team programming contest -- should not be one of them. I have no objection to the following online contests: International Olympiad in Informatics (IOI), Google Code Jam (GCJ) final, Facebook Hacker Cup (FBHC) final, and any similar contest final which is participated by the best ~20 competitive programmers in the world. What makes them different from ICPC is the amount of trust we have put in th...

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OCPC 2025 Summer season — wrap Hi everyone! <center><a href="https://ocpc.camp"><img src="https://ocpc.camp/images/ocpc_light.svg" height="100px"></a> <a href="https://icpc.foundation/"><img src="/predownloaded/43/08/43086529a28ccb5c9f2f2eec560ffa85e09c6881.svg" height="100px"></a></center> Just recently, the last mirror of the summer season of OCPC 2025 has concluded. I would like to take this moment to share some of the details and statistics on how it went with the community &#128522; [cut]<br> ### ICPC award Okay, this happened last chronologically, but it's probably most relevant, so I will start with it! <center> <a href="/predownloaded/43/df/43dfc0edaaa29db59b2b5ba6afbd4f033c8b535f.jpg"><img src="/predownloaded/43/df/43dfc0edaaa29db59b2b5ba6afbd4f033c8b535f.jpg" height="200px"></a> <a href="/predownloaded/b9/25/b9256e789a31ab2d1b3858bfa984ea1341dbc6c5.jpg"><img src="/predownloaded/b9/25/b9256e789a31ab2d1b3858bfa984ea1341dbc6c5.jpg" height="200px"></a> <a href="/predownloaded/c5/21/...

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2018 ICPC Asia Jakarta Regional Contest problemset on (now Codeforces) Gym **UPD: 2018 ICPC Asia Jakarta Regional Contest problemset is now available on CODEFORCES Gym** **UPD2:** The original checker for [problem C](https://mirror.codeforces.com/gym/102001/problem/C) turns out to have non-deterministic behaviour due to insufficient array size. Fortunately, the false checking caused by the bug occurs rarely enough that the live contest (including the mirror in Codeforces) was not impacted (at least we did not receive complaints on the live contest). The checker was fixed on 23 June 2020 and all submissions have been rejudged. See [this comment](https://mirror.codeforces.com/blog/entry/63220?#comment-598987) for more detail. We would like to invite you to the [mirror post-contest of 2018 ICPC Asia Jakarta Regional Contest](https://mirror.codeforces.com/gym/102001). The contest will start on [Sunday, 25 November 2018, 10.00AM Western Indonesian Time (UTC+7)](https://www.timeanddate.com/worldclock/fixedtime.html?msg=2018+ICPC+Asia+Jakarta+Regional+mirror+post-contest&iso=20181...

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My story at ACM ICPC World Final 2016 My team (me + [user:flashmt,2016-05-20] + [user:nguyenhungtam,2016-05-20]) was probably never noticed by anyone, but we were actually aiming for medal. And I think we performed ok in the final, ending up at #15, still need some more luck & brain to win a medal. Anw, I decided to share my story. Btw if you are Vietnamese, you can also read [this](https://www.facebook.com/notes/thanh-trung-nguyen/t%C3%B3m-t%E1%BA%AFt-acm-world-final-2016/1157851804228014?pnref=story). Back story ========== In the ACM history, a Vietnamese team has never won any WF medal. 5 years ago, team of [user:ktuan,2016-05-20] (only Vietnamese red target on Topcoder) had high hope, but ended up at #17. 4 years ago, team of [user:ConanKudo,2016-05-20] also had high hope, but messed up in the first 3 hours and ended up at #17. So I really wanted to win medal. And I've been planning for this World Final for several years.. Team formation ============== I've chosen [user:flashmt,2016-05-20] as teamm...

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[IOI 2025] How Is It a Disaster Already? I am the Deputy Leader for the Indonesia IOI 2025 delegation this year. I can't fathom how IOI 2025 has gone so horribly wrong before IOI has even started. Firstly, I will share the experiences of the Indonesia team when traveling/arriving in Bolivia. Afterwards, I will mention some accounts provided by other countries about their struggles in Bolivia. Before the journey even began, BoA cancelled one of the only flights from Sucre to Santa Cruz during the departure day, we are a bit concerned about the alternative flight as the transit time is only 1h10m especially after our recent experiences. Our team's journey began on July 23rd before dawn, flying from Jakarta to Sao Paolo, we arrived the evening of July 23rd in Brazil without a hitch. The following afternoon (July 24th), we got on our flight from Sao Paolo to Santa Cruz, departing at 14.00. During our check in process, we had to wait for some time because they were checking our documents (I would say roughly 15-45 mi...

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OCPC 2025 Summer Hi everyone! <center><a href="https://ocpc.camp"><img src="https://ocpc.camp/images/ocpc_light.svg" height="100px"></a> <a href="https://icpc.foundation/"><img src="/predownloaded/43/08/43086529a28ccb5c9f2f2eec560ffa85e09c6881.svg" height="100px"></a></center> <center> <b>Supported by</b><br> <a href="https://www.janestreet.com/join-jane-street/open-roles/?type=students-and-new-grads&location=london"> <img src="/predownloaded/ee/f2/eef26616a3661c658d1545f18ed21fabb14d5871.svg" height="60px" style="margin: 10px 10px 10px 10px;"></a> <a href="https://pinely.com/"> <img src="/predownloaded/0a/0f/0a0f3f67435d1f6e467bc7203d4a2090ba8f92cc.svg" height="60px" style="margin: 10px 10px 10px 10px;"></a> </center> ... And a happy May day! We are very happy to announce that OCPC (formerly, the _Osijek Competitive Programming Camp_) is back this Summer, on **June 21-29, 2025**! While the dates are pretty tight, they appear to be the ones that are most suitable (among all the summ...

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Teams going to the 2024 ICPC Asia Pacific Championship Starting from this year, the ICPC Asia Pacific region will has a new super-regional/semifinal/playoff contest called "The ICPC Asia Pacific Championship” (see relevant discussion [here](https://mirror.codeforces.com/blog/entry/118552)). Here is the list of all participating teams according to the [official website](https://icpc.asia/). If you know the Codeforces handles of any team that is not yet filled in, please let me know so I can add them. ## Invited Teams <style type="text/css"> .tg {border-collapse:collapse;border-spacing:0;} .tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; overflow:hidden;padding:10px 5px;word-break:normal;} .tg th{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; font-weight:normal;overflow:hidden;padding:10px 5px;word-break:normal;} .tg .tg-0lax{text-align:left;vertical-align:top} </style> <table class="tg"> <thead> <tr> <t...

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Teams going to the 2025 ICPC Asia Pacific Championship This year, the 2025 ICPC Asia Pacific Championship will be hosted by National University of Singapore. The list of 65 qualified teams was posted on the [official website](https://icpc-apac-2025.vercel.app/competition/teams). If you know the Codeforces handles of any team that is not yet filled in, please let me know so I can add them. ## Invited Teams <style type="text/css"> .tg {border-collapse:collapse;border-spacing:0;} .tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; overflow:hidden;padding:10px 5px;word-break:normal;} .tg th{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; font-weight:normal;overflow:hidden;padding:10px 5px;word-break:normal;} .tg .tg-0lax{text-align:left;vertical-align:top} </style> <table class="tg"> <thead> <tr> <th class="tg-0lax">Regional</th> <th class="tg-0lax">Institution</th> <th class="tg-0lax">Team</th> ...

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Online mirror of The 2023 ICPC Asia Jakarta Regional Contest Hello Codeforces! We are going to hold The 2023 ICPC Asia Jakarta Regional Contest. We invite you to join the online mirror contest [2023-2024 ICPC, Asia Jakarta Regional Contest (Online Mirror, Unrated, ICPC Rules, Teams Preferred)](https://mirror.codeforces.com/contests/1906) on Codeforces. It will be held on [contest_time:1906] and will last for 5 hours. The mirror will be held using ICPC-style scoring with 10 to 13 problems. The problem statements will only be available in English. We encourage participating as a team using only one computer for coding (as in ICPC contests). The mirror will be unrated. Some useful links: * [The 2023 ICPC Asia Jakarta homepage](https://competition.binus.ac.id/icpc2023) * [The regional information in ICPC Global](https://icpc.global/regionals/finder/Jakarta) * [The onsite scoreboard](https://competition.binus.ac.id/contest/public) We hope that you will enjoy the contest. Good luck and have fun! **UPD.** The mirror has started! You can...

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Live online mirror of The 2019 ICPC Asia Jakarta Regional Contest Hi, We would like to invite you to participate in the live (with 30-minute delay) [online mirror contest of The 2019 ICPC Asia Jakarta Regional Contest](https://mirror.codeforces.com/contest/1252) ([our regional website](https://competition.binus.ac.id/icpc2019/), [our regional in ICPC website](https://icpc.baylor.edu/regionals/finder/Jakarta-2019), [official contest portal](https://competition.binus.ac.id/contest)) this weekend. The online mirror contest will start on [contest_time:1252]. The contest consists of several problems and you can solve them in 5 hours. See you on top of the leaderboard. **UPD1:** Thanks for participating. The problems should be available for upsolving. The soft-copy of the problem analysis (the same as the one distributed to all contestants during the awarding ceremony) is available [here](https://github.com/jonathanirvings/icpc-jakarta-2019/blob/master/problem_analysis.pdf). **UPD2:** The full problem repository is available [here](https://github.c...

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Teams going to the 2026 ICPC Asia Pacific Championship The 2026 ICPC Asia Pacific Championship will be held in Taoyuan, Taiwan, on March 8. For more information, please visit the [official website](https://apac26.icpc.tw). This post is based on the list of 70 qualified teams published [here](https://apac26.icpc.tw/championship/latest/teams/). If you know the Codeforces handles of any team that is not yet filled in, please let me know so I can add them. Additionally, here are some useful links: - **Livestream:** https://www.youtube.com/live/5x29584WxXg?si=PQ6-yýLTOE3Xp7c3 - **Online Mirror:** https://mirror.codeforces.com/blog/entry/151816 - **Live Standings:** https://icpcapac.firebaseapp.com/standings/ The on-site contest starts at **09:30 (UTC+8) on March 8, 2026**. Best of luck to all teams competing in the championship! ## Invited Teams <style type="text/css"> .tg {border-collapse:collapse;border-spacing:0;} .tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px...

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OCPC Summer 2025 Indonesia Mirror Camp Hello everyone! <center><img src="/predownloaded/d9/d0/d9d04ba5a2b7877f55c8e11c0e277a637da23adc.png" width="500px"></center> We are very excited to announce that Indonesia will be hosting an official mirror camp of the [OCPC 2025 Summer](https://mirror.codeforces.com/blog/entry/142531), and it is open to teams from around the world! The mirror camp will be held on **August 15th-23rd, 2025**, which was chosen to be shortly before the ICPC World Finals. The camp is hosted by BINUS University in Jakarta. As this is a mirror camp, all the problem sets are the same as the main OCPC camp in Bucharest. Although we chose this date to prepare for the ICPC World Finals, the camp is open for every teams, both ICPC World Finalists and teams who aspire to become the next World Finalists. Registration and Content ------------------------ The participation fee for this mirror camp is **201 EUR per team** (roughly 3.8 millions IDR). Note that this fee does not include costs for accommo...

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OCPC x GoForGold — ICPC India Elite Camp Hi everyone\! <center style="display: flex;align-items: center;"> <img height="70px" src="/predownloaded/67/2f/672f239a4b390e85db2408790f5907770547fdb2.jpeg"> <img height="65px" src="/predownloaded/6b/b4/6bb4c1baf053e08ac2257bee4fe8c479b133272b.png"> <img height="70px" src="/predownloaded/31/ec/31ec29a58f0f4b10b0cb9a0ae1800c0174d0e1fe.svg"> </center> We're excited to share some great news for the international competitive programming community. For the first time, India will be hosting an official [OCPC](https://ocpc.camp) mirror camp this summer, and it's open to teams from around the world\! **OCPC x ICPC India Elite Camp 2025** will be held from July 21st-29th 2025 at NST ADYPU Campus in Pune, organized by GoForGold in collaboration with ICPC India. This is part of the international OCPC training circuit, which means we'll be using the same contest sets as the main OCPC camp in Bucharest. ## **Who can participate?** **ICPC World Finalists** \- Registration fee w...

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Online mirror of The 2025 ICPC Asia Jakarta Regional Contest Hi Codeforces, We are going to hold The 2025 ICPC Asia Jakarta Regional Contest. We invite you to join the mirror on TLX! Key details: - Unrated - Contest link: [ICPC Asia Jakarta Regional Contest 2025 (Mirror, Unrated)](https://tlx.toki.id/contests/icpc-jakarta-2025-mirror) - Time: [Sunday, November 23rd, 2025 at 03:30 UTC](https://www.timeanddate.com/worldclock/fixedtime.html?msg=ICPC+Asia+Jakarta+2025&iso=20251123T1030&p1=108&ah=5) - Duration: 300 minutes - Problems: 10-13 Some useful links: * [The 2025 ICPC Asia Jakarta homepage](https://competition.binus.ac.id/icpc2025) * [The regional information in ICPC Global](https://icpc.global/regionals/finder/Jakarta) * [The onsite scoreboard](https://competition.binus.ac.id/contest/public) We hope that you will enjoy the contest. Good luck and have fun!

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Preview: Taiwan NU Only two previews remaining, and today’s team is National Taiwan University +1 ironwood branch. This team already participated in World Finals in 2011 and had not won medal with 6 problems solved, but they make good use of this 2 years with outstanding progress in both personal and team competitions. In 2010 team finished 3rd in Kaohsiung and 1st in Jakarta Regional Contests. In 2011 they placed 1st in Kuala Lumpur and 2nd in Hsinchu Regional Contests, but another team from the same university was selected. In 2012 they won both Kaohsiung and Jakarta Regional Contests. After Jakarta regional they were interviewed, you can view it [here](http://www.youtube.com/watch?v=h6B6Vjtcyf4). ![ ] (https://r.mail.yandex.net/url/AetkRfDx1RE-mFt_070vuQ,1372354928/lh5.ggpht.com%2F-cZTIuky8oYE%2FTeL0Gtek7HI%2FAAAAAAAEBOw%2F3we5RWiaTG0%2F_4949348.jpg) Line-up: **Pi-Hsun Shih** &mdash; Codeforces rating [2823](/profile/peter50216), TopCoder rating [3158](http://community.topcoder.com/tc?...

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About Teams Participating in Online Mirrors of ICPC-Style contests It is well known that in onsite ICPC contests, the team members have to share one computer. However, I've been always confused that whether it is also true for Codeforces online mirrors of ICPC-style contests. I have chosen two of the ICPC-ruled contests on Codeforces. [COMPFEST 15 &mdash; Preliminary Online Mirror](https://mirror.codeforces.com/contests/1866): As mentioned in [this comment](https://mirror.codeforces.com/blog/entry/119883?#comment-1064891), all teammates are **allowed** to use their three different computers at the same time. [Online mirror of The 2023 ICPC Asia Jakarta Regional Contest](https://mirror.codeforces.com/contests/1906): As mentioned in the [announcement](https://mirror.codeforces.com/blog/entry/122754), it is **encouraged** to participate as a team using only one computer for coding. Since currently there is no annoucement for the coming online mirror of 2024-2025 ICPC, NERC, Southern and Volga Russian Regional Contest, I sincerely ask here: is it allowed for each team membe...

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TLX Open Contest Beta Round #1 — Invitation Hi all, This year, Indonesia is hosting [Asia-Pacific Informatics Olympiad 2015](http://apio2015.org/). For this competition, we will use our brand new contest system called [TLX](https://competition.ia-toki.org/). We have been using TLX intensively for Indonesian training camps and so far we have been very satisfied and no major problems were encountered. Now, we would like to conduct a real-time test for international usage. So, we invite you to take part in **TLX Open Contest Round #1**. Here are the details: - Saturday, April 25 20.00 UTC+7 &mdash; 23.00 UTC+7 (3 hours) [timeanddate](https://www.timeanddate.com/worldclock/fixedtime.html?msg=TLX+Open+Contest+Beta+Round+%231&iso=20150425T20&p1=108&ah=3). - You have to register to TLX (there is an SSO login system), and then register to the contest. - Contest registration closes 5 minutes before contest **ends**. - IOI-style, 3 problems. There will be subtasks. For this testing round, we will be using past Indonesian olymp...

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National University of Singapore Team @ ICPC World Finals 2019 Disclaimer: I'm a curious student from National Taiwan University. Reference: https://algorithmics.comp.nus.edu.sg/ According to the first section, **3body2** ([user:sidhant,2019-01-26], [user:btzy,2019-01-26], [user:bayweiheng,2019-01-26]) will go to ICPC World Finals 2019. However, according to the published rule in _ICPC Selection Contest For Regionals 2018_ section, **Send Bobs to Alice** ([user:alexa0704,2019-01-26], [user:MofK,2019-01-26], Tran Tan Phat) should go instead. Anyone know the story? ### Details According to [the blog of C. J. Hwang.](http://blog.sina.com.cn/s/blog_b946da100102zal7.html), NUS have 3 qualified teams: **Send Bobs to Alice**, **3body2**, and **Pandamiao**. The NUS rule said the team with lowest _score_ wins, where _score_ is (NUS rank of Singapore Preliminary-1)*1.1 + (NUS rank of Jakarta/Nakhon Pathom/Yangon-1)*2 + (NUS rank of Singapore-1)*2.9. Here are the scoreboards: - Singapore preliminary: https://asiasg18-prelim.kattis.com/st...

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Gym Contest with Editorial While giving team contest we try to find Gym contest which has editorial available, but it takes plenty of time for finding such contests. ( We can add a gym contest to a personal group and look at others submission but still, editorials are more effective) So I thought of making a list of Gym Contest which has editorials available. Can you help me make a list of such contests? Thanks in advance. Happy Coding :) ---------------------------------------------------------------------------------- Contest List: 1. [Hello 2015 Div. 1](https://mirror.codeforces.com/gym/100570) 1. [2017 Bangladesh National High School Programming Contest](https://mirror.codeforces.com/gym/101353) 1. [2018 KAIST Run Spring Contest](https://mirror.codeforces.com/gym/101806) ( [Editorial](https://drive.google.com/file/d/1xzmcmlPLFd4FK5H0waZdg5zjrzRJs8Cf/view) ) 1. [BAPC 2013](https://mirror.codeforces.com/gym/100625) ( [E...

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Candidate Teams to the 2025 ICPC Asia Pacific Championships Since the Seoul regional has concluded, I've compiled a list of teams expected to compete in the [2025 APAC Championship](https://icpc.asia/) based on the current situation and the [selection rules](https://icpc.iisf.or.jp/asia-pacific/2024-2025-cycle/): - https://icpcapac.solved.ac/2025 The Site scores for each of the five sites are also included, and the values are: - **Taichung** (17 Nov): **74.26** - **Seoul** (23 Nov): **76.34** - **Jakarta** (1 Dec): **86.16** - **Hanoi** (13 Dec): **104.10** - **Yokohama** (22 Dec): **71.50** Details for the calculation can be viewed on the site. 65 teams will be advanced/invited. Our team is currently 66th on the list, please wish us luck: 

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LIGHT ROBOT DETECTOR (my problem creation) COPYRIGHT : ALBERTUS KELVIN (Jakarta,Indonesia) ================== in a mirror space there are N mini robots which are sent to develop a new robot's kingdom. Each robot has one light detector so if there is a light come or pass through this detector, the robot will be shown in the mirror. From the planet A, is sent a major robot which can detect some robots (N robots or less than N robots) with it's component namely light source which can be reflected in the mirror in that planet. The function of this major robot is to detect the location of the other robots. In this case what i mean as the light case is about the reflection in physics. Also we must use the rule : the coming angle must be same as the pass angle. INPUT The program is inputed by a single line contains two integers R and C, which show us about the row and column value respectively. Follow by R rows which each row contains C characters , where you may use '#' as the mirror, '.' as the free space of the pla...

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TLX Open Contest Beta Round #2 Hi all, Last week, we conducted [TLX Open Contest Beta Round #1](http://mirror.codeforces.com/blog/entry/17533) Now, want to invite you to take part in **TLX Open Contest Round #2**. The details are similar to the previous contest. To reiterate: - Saturday, May 2, 20.00 UTC+7 &mdash; 23.00 UTC+7 (3 hours) [click here for other timezones](https://www.timeanddate.com/worldclock/fixedtime.html?msg=TLX+Open+Contest+Beta+Round+%232&iso=20150502T20&p1=108&ah=3). - [Registration opens here](https://competition.ia-toki.org/contests/17/view). If you don't have account, you will be prompted to register (there is an SSO login system). - Contest registration closes 5 minutes before contest **ends**. - IOI-style, 3 problems. There will be subtasks. For this testing round, we will be using past Indonesian national olympiad problems. - Available languages are C, C++11, and Pascal. - Full scoreboard will be available. - Full feedback for each submission. - You may submit clarifications on the fi...

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Help in Merge Not Sort https://mirror.codeforces.com/contest/1906/problem/E This is the link to the problem E of 2023-2024 ICPC, Asia Jakarta Regional Contest (Online Mirror, Unrated, ICPC Rules, Teams Preferred) , can anyone help me in understanding the intuition and logic behind the dp approach of this problem. I cannot seem to grasp the logic behind the problem. Any suggestion/idea maybe helpful too!!

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Need help on ICPC Asia Jakarta Regional Problem This is the problem url: https://mirror.codeforces.com/problemset/problem/1906/M I can't understand the editorial of this problem. Specifically I don't understand the second scenario, how can we conclude M <= 2 * (S &mdash; M) will hold after one move. According to me, if the value of M is reduced by 0 or 1 and S is reduced by 3, this condition should not hold.

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what that means ? I was looking the register list for the 2023-2024 ICPC Asia Jakarta Regional Contest (Online Mirror, Unrated, ICPC Rules, Teams Preferred), and I noticed that some teams or participants were highlighted in red. I am curious about the significance of this color, whether it indicates a bug or if there is a special reason behind it ?

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Jakarta Regional 2014 , Problem G : Prime Switch, some help? [Problem](http://competition.binus.ac.id/icpc2014/ps/icpc14jak-g.pdf) Some help/hint would be greatly appreciated :)

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help with problems someone who has solved this problem can help me, give me some idea :( It's a problem from reginal ACM in jakarta 2013 https://icpcarchive.ecs.baylor.edu/index.php?option=com_onlinejudge&Itemid=8&category=596&page=show_problem&problem=4449

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