ahmed_aly's blog

By ahmed_aly, history, 4 years ago, In English

I'm sadly announcing that a2oj.com (A2 Online Judge) will be retiring by end of 2019, I'll shut it down at midnight on New Year's Eve. It was something I took care of for about 10 years.

I'm really sorry, but I prefer not to explain my reasons, so please don't ask me why I'm doing this, it was hard enough for me to make this decision, and also please don't try to convince me to change my mind.

I'd like to say thank you to everyone who used it, and please accept my sincere apologies for shutting it down.

If you have something good to say about A2OJ (how you used it or how it helped you in any way), I'd love to read that, please send it to the following email (or in a comment here): [email protected]

Also please feel free to take a copy of any data you can access, and if you need some data in a specific format, please send your request to the following email: [email protected] (if the data isn't public, make sure to send from your registered and verified email which can access this data). I'll do my best to fulfill all requests.

Please only use the above email, because soon I'll be deactivating my personal Facebook account again, I'll also deactivate A2 Online Judge.

Edit 1: I'll keep a static version of all Ladders & Categories.

Edit 2: Here's how I generated the ladders, in case if anyone wants to implement it: https://codeforces.com/blog/entry/47442

Edit 3: A2 Online Judge is shut down now, and a static version of all ladders and categories is available. And here are some final numbers for the record:

Database numbers:

  • 24,012,628 total number of database rows.
  • 99,242 registered users.
  • 33,133 created contests.
  • 1,581,430 submissions collected from other online judges.
  • 937,658 different source codes stored in the database.
  • 261,733 compiled and executed source codes (in 54 different languages).
  • 6,144,545 user solved problem entries (detected that a user solved a problem).
  • 377,580 problems added to contests.

Google Analytics numbers:

  • 30,265,387 page views.
  • 5,252,045 sessions.
  • 1,157,668 users.

Top 10 countries from Google Analytics:

  1. India
  2. Egypt
  3. Brazil
  4. United States
  5. Bangladesh
  6. Peru
  7. Jordan
  8. Syria
  9. Colombia
  10. Bolivia

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By ahmed_aly, history, 5 years ago, In English

ltaravilse, he was that kind, funny and super helpful guy. I'm sure many of us interacted with him some how, and I was lucky to meet him in person more than once. Everyone from the old TopCoder days should remember him.

Sadly, and I still can't believe it, he passed away yesterday. This is a really sad event for the whole competitive programming community. People from South America can tell more about how kind and helpful he was.

MikeMirzayanov, can we please have a round in his name?

Rest in peace my dear Leo.

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By ahmed_aly, history, 6 years ago, In English

Over a year ago I created some ladders on A2OJ, you can read the details of these ladders here.

Some people asked me to create more similar ladders, so for each rating range I created another ladder using a similar criteria which I used for the old ladders, with 200 problems in each ladder and none of them exists in any of the old ladders (they are bit harder than the old ladders).

Also I added another feature, now you don't need to go and click on the link in A2OJ to update your solved problems, all what you need to do is to include your Codeforces handle in your account page, join the ladder and start solving, once you solve a problem, A2OJ will detect that within a minute or so.

I have a small request if you are reading this and practiced using the old ladders, please let me know in a comment if these ladders really helped you, also please let me know if you have any suggestions, and thanks a lot in advance.

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By ahmed_aly, history, 6 years ago, In English

i need 4 original problems similar to div2 a, b, c & d. i'm willing to pay in dollars if i use your problems. if you can get some original problems 100% ready within 24 hours, please send me a private message.

edit: i already got a lot of responses, thanks everyone

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By ahmed_aly, history, 7 years ago, In English

I always wanted to make something like a guide for anyone who wants to be better at competitive programming. But I believe that I'm not experienced enough to make this guide.

So, here is what I did and I hope it will be helpful to many of you:

  • Out of more than 80,000 rated Codeforces users, I selected just 700 of them who satisfied the following conditions:
  1. Over the period of 1-2 years, their rating increased step by step more than 600 points in total (their graph looks linear in a period of 1-2 years with increment of more than 600 points).
  2. They participated in at least 20 rated contests.
  3. They solved at least 150 problems in practice in this period.
  • For each rating range, interestingly I found many common problems solved by these users when their rating was in that range. I found the most 100 solved problems in that rating range.

  • I created a ladder for each range, and the problems inside it are sorted based on an accurate difficulty level I calculated.

I believe if someone manages to solve (or at least understands the solution from someone else or the editorial) all these problems, they will notice some significant improvements in their skills and rating.

You can find the ladders at the top here: https://a2oj.com/ladders

Also please share this with anyone who might be interested.

P.S. I know that a ML model might do a better job, but the reason why I didn't do this, because I didn't have enough data.

[Edit] I created more ladders, you can read about that and other new feature here.

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By ahmed_aly, history, 7 years ago, In English

I can't really describe how happy I'm because of all the support I got from everyone. Huge thanks to everyone!

Yesterday I successfully finished migrating the website to AWS, and it's running now. I know there are some bugs/issues needs to be done, and to do the promised rewards, I'll do that as soon as possible.

Thanks a lot everyone!

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By ahmed_aly, history, 7 years ago, In English

Hello everyone,

Several people are asking me when A2 Online Judge is coming back, and unfortunately the issue this time might take longer to fix it.

This is the server which was hosting the website in my garage for several years:

A2 Online Judge server

And I think it's time to move to the cloud, but this requires some money. I created a campaign to raise $3000 which I need to host it on AWS for the next 3 years at least. You can read more details here: https://www.gofundme.com/support-a2oj

Please support to bring the website back, even if by just sharing the campaign.

Thanks in advance,

Ahmed Aly

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By ahmed_aly, history, 8 years ago, In English

I'm working on a chat bot that will look like this (watch the video): https://goo.gl/OsSdb3

I still have a lot of work to do, and I'll wait for Facebook approval to make this available to everyone which might take weeks.

I have countless number of ideas, it can be something like your virtual coach who suggests problems to solve or editorials/algorithms to read, which remembers your history and suggests something suitable for you.

In the above page you can subscribe to get an email when this is live to everyone, but what I need the most right now, is ideas. Please if you have any idea, you can write it in the above link or just write it in a comment here. Thanks in advance.

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By ahmed_aly, history, 8 years ago, In English

After running the contest in the past 4 years, I'm back to participate as a contestant again in Google Code Jam. And since I almost didn't solve problems recently, so I wanted to make few warmups for Code Jam.

I will make a short daily warmup contest until Code Jam qualification round, and after the qualification round I'll make it less frequent. Each contest will be 2 hours long, and will contain 5 problems. All problems will be from Codeforces. Until the qualification round, I'll select easy-medium problems, and after that I'll select harder problems, the problems difficulty will be similar to the difficulty of the coming Code Jam round.

I'll start with 4 contests starting from tomorrow, one every day and they will start at the same time.

Here are the first 4 contests:

Edit 1: The first contest is over, with 35 contestants who made at least 1 submission, and 200 submissions in total. It was a good warmup for me.

ِEdit 2: The second contest will start in 30 minutes. http://a2oj.com/contest?ID=24958

ِEdit 3: The third contest will start in 30 minutes. http://a2oj.com/contest?ID=24959

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By ahmed_aly, 9 years ago, In English

Unfortunately, for technical reasons, my scoreboard will not work.

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By ahmed_aly, 9 years ago, In English

Recently I added a new feature in A2 Online Judge, it's called Practice Ladders. A practice ladder is just a list of problems, and you can add some dependencies between the problem (for example, you must solve problem X before being able to see problem Y). Also you can add dependencies between the ladders and each other (for example, you must solve all problems in ladder X before being able to see any problem in ladder Y).

Also I created 7 Codeforces practice ladders which should you to increase your level, each ladder contains 100 Codeforces problems. Find which ladder is appropriate for you and enjoy!

Div. 2 A Problems: http://a2oj.com/Ladder.jsp?ID=4

Div. 2 B Problems: http://a2oj.com/Ladder.jsp?ID=5

Div. 2 C Problems: http://a2oj.com/Ladder.jsp?ID=6

Div. 2 D Problems: http://a2oj.com/Ladder.jsp?ID=7

Div. 2 E Problems: http://a2oj.com/Ladder.jsp?ID=8

Div. 1 D Problems: http://a2oj.com/Ladder.jsp?ID=9

Div. 1 E Problems: http://a2oj.com/Ladder.jsp?ID=10

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By ahmed_aly, 9 years ago, In English

I'm planning to make a scoreboard for the ACM ICPC World Finals 2015, the scoreboard will contain the TopCoder and Codeforces handles for the contestants. It will be similar to this one (but with some more improvements).

Please post the Codeforces handles for the qualified teams here. I'll keep updating this post once I get any new information.

Any suggestions for the scoreboard are welcome for sure.

I'll add all the handles I get in the following table:

Country University Contestant 1 Contestant 2 Contestant 3
1 Russia St. Petersburg National Research University of IT, Mechanics and Optics tourist qwerty787788 VArtem
2 Japan The University of Tokyo rng_58 semiexp wrong
3 China Shanghai Jiao Tong University BaconLi rowdark yefllower
4 Russia Moscow State University TeaPot GlebsHP meshanya
5 Poland Jagiellonian University in Krakow piob guspiel m.sewcio
6 Ukraine Lviv National University RomaWhite witua I_love_Tanya_Romanova
7 Croatia University of Zagreb ikatanic stjepan gustav
8 United States University of Southern California cgy4ever ghostgold innovator
9 China Fudan University flydutchman Riatre this_isssssyy
10 United States Massachusetts Institute of Technology surwdkgo sillycross ACube
11 Russia National Research University Higher School of Economics aid yurboss i.trofimow
12 China Tsinghua University ACMonster Leo_Yu Eternal_Answer
13 Sweden KTH — Royal Institute of Technology Gullesnuffs simonlindholm jsannemo
14 Iran Sharif University of Technology mR.ilchi haas LGM
15 Belarus Belarusian State University kolesov93 qwaker.00 nekrald
16 Russia St. Petersburg State University Copymaster Seemann KapJI
17 Ukraine Odessa National Mechnikov University Monyura Sfairat Sklyack
18 Japan University of Tsukuba logicmachine zerokugi nuip
19 Japan Kyoto University natsugiri ichyo eha
20 Romania University of Bucharest freak93 scipianus
21 China Zhejiang SCI-TECH University Nero problem-solved JayYe
22 United States Carnegie Mellon University iridescent AstroConjecture aquamongoose
23 Ukraine Taras Shevchenko Kiev National University Fdg Furko M0sTik
24 China Beihang University sd0061 InheritO InheritG
25 China Peking University chnlich wuzhengkai zcwwzdjn
26 South Korea Korea University Myungwoo Cauchy_Function wclee2265
27 Poland University of Warsaw mareksom Errichto johnasselta
28 South Korea KAIST mjy0503 etaehyun4 protos37
29 Singapore National University of Singapore jonathanirvings nathanajah darknsux
30 Russia Saratov State University IlyaLos ikar fcspartakm
31 United States University of Central Florida edorundo jcomputer000 tylerbrazill
32 Georgia Free University of Tbilisi svanidz1 TMandzu guliashvili
33 China University of Electronic Science and Technology of China hlwt qph-Jeremy xiaoke
34 Singapore Nanyang Technological University sillyboy con_nha_ngheo ddldyj237
35 China Beijing Institute of Technology nono s0en1it YYOne
36 Canada University of Waterloo dojiboy9 vlyubin goffrie
37 Brazil Universidade de São Paulo StefanoT marcoskwkm antonio_junior
38 Taiwan National Taiwan University fenzhang lnsuyn Nekosyndrome
39 China Fuzhou University lastenX L_Ecry yoooou
40 Czech Republic Charles University in Prague fhlasek simsa.st mirecek3
41 India Indian Institute of Technology — Roorkee adurysk amankedia1994 noah07
42 Russia Moscow Institute of Physics & Technology ssmike kuzmichev_dima pershik
43 United States University of Michigan at Ann Arbor WCG archerundead CLDP
44 Argentina Universidad de Buenos Aires — FCEN zylber tavo92 melsclar
45 Poland University of Wroclaw bardek Solaris matix2267
46 South Korea Seoul National University zlzmsrhak pjsdream lemonsqueeze
47 China Zhejiang University chnluyi Dark_sun zimpha
48 Colombia Universidad Nacional de Colombia — Bogotá niquefa_diego DiegoCR lemur
49 China South China University of Technology Xiaodongdong yada nf001
50 India Indian Institute of Technology — Madras Sundar ajkrish95 vkarthik195
51 Vietnam University of Engineering and Technology — VNU net12k44 Aquacloud ntit_co1
52 China Beijing Normal University pkwv suiyuan2009 hwq1352249
53 China Beijing Jiaotong University kybconnor Ryan_MuQ Lquartz
54 China Shanghai University meijun kuangbin zhangxiaohao
55 Spain Universitat Politècnica de Catalunya dirbaio etal angargo
56 China Huazhong University of Science & Technology HUST_LAZ Hellis once8203
57 Kazakhstan Nazarbayev University ADJA An4ik.D kt-9
58 United States Stanford University csimstu simp1eton 6kkdrx3
59 Bangladesh Jahangirnagar University nfssdq FlaminRage bhadra
60 Russia Saint Petersburg Academic University – Nanotechnology Research and Education Centre RAS nk.karpov evgentu geka666
61 Belarus Belarusian State University of Informatics and Radioelectronics tanas asmisha dberezhnov
62 Switzerland ETH Zürich m.raszyk schorsch andrei.prv
63 Egypt The American University in Cairo ghooo Hosam_Samy islamdiaa
64 Indonesia University of Indonesia Gyosh sokokaleb athin
65 Germany Friedrich-Alexander-University Erlangen-Nuremberg pwild tobias.polzer MiriTheRing
66 India International Institute of Information Technology — Hyderabad viv001 karanaggarwal pulkitg10
67 Bangladesh Shahjalal University of Science and Technology Corei13 J-C PlausibleDeniability
68 China Jilin University tjmts chm517 yaoyan5
69 Iran University of Tehran A.Elahi Leyla NIWIS
70 Canada University of Calgary yum EACoder karklenator
71 Brazil Federal University of Minas Gerais gpoesia
72 Australia University of New South Wales junkbot yujinwunz KKOrange
73 Egypt Arab Academy for Science and Technology (Alexandria) adelnobel MoustafaMaher Haytham.Breaka
74 Brazil Universidade Federal de Campina Grande deMatos rafaelclp Manoel
75 India Indian Institute of Technology — Kharagpur anuraganand biswajitsc sayhellotoanshu
76 United States University of California at Berkeley jx_wuyi Jby_Yeah xfastx
77 United States University of Minnesota — Twin Cities HidenoriS GoldenGopher nil_mo
78 China National University of Defense Technology clavichord93 alpc128 qwdqkh1
79 Denmark University of Copenhagen Tejs Thomas_Ahle JakobTejs
80 South Africa University of Cape Town h4tguy rspencer MrHamdulay
81 Belarus Belarusian State Economic University sas4eka Liaksiejka hired777
82 United States Virginia Tech Wertle miraziz spruett3
83 Russia Kazan (Volga Region) Federal University dinarisio RamTararam OmniLRenegadE
84 Egypt Faculty of Computer and Information Sciences, Ain Shams University zetamoo ahmedameen xa.mohsen
85 Cuba Universidad de La Habana mnaeraxr jcg otero1991
86 Russia Moscow Aviation Institute Timus lester
87 Iran Yazd University of Iran A.K.Goharshady saeedtame
88 Venezuela Universidad Simón Bolívar p-space avatar_tp josegpg
89 United States University of Maryland Solej
90 Egypt Cairo University — Faculty of Computers and Information moh.amr mc_mosa AhmedHamed
91 China University of Science and Technology of China wilsonlym mynameisverylong ufo172849z
92 United States University of California Los Angeles lcch MatRush gaoxin
93 United States University of Chicago hweigel528
94 Argentina Facultad de Ciencias Exactas-Universidad Nacional de Rosario karupayun mariano22 martinv
95 Egypt Faculty of Engineering, Ain Shams University TsunamiNoLetGo ahmed_fathy_aly Alwahsh
96 Georgia Georgia Institute of Technology oioi98
97 China Hangzhou Dianzi University HunDunDM zhouxianjie
98 Brazil Universidade Federal do Rio de Janeiro rodrigozhou filipe.zhou diegoximenes
99 India Amrita School of Engineering, Kollam ash1794 lighters Skr379
100 Brazil Universidade Estadual de Campinas igorwr soneca ruansilva
101 Mexico Escuela Superior De Computo Instituto Politecnico Nacional Garo9521 ChOmPs
102 Egypt German University in Cairo TheSavageKoder Mohamed.Bassem .Khaled.
103 Peru Universidad Católica San Pablo jainor alculquicondor darkloz
104 India Indian Institute of Technology — Delhi TheTerminalGuy knsn
105 Bolivia Universidad Privada de Santa Cruz de la Sierra alexpizarroj josemanuel101 Ademord
106 Australia The Australian National University aandrew
107 Cuba Universidad de Oriente — Sede Antonio Maceo gilcu3 JoMoPinyol
108 Morocco Al Akhawayn University magieNoire __builtin__wolfy CloverAsta
109 Syria Tishreen University BayHarborButcher samiemad majd.gda1
110 Mexico Universidad Autónoma de Aguascalientes flavio FraNkoAL jarl93
111 Iran Shahid Beheshti University m.haghpanah farzad.shbfn nima.sh
112 United States Cornell University edufgf victoreis marinheiro
113 Morocco ENSA Marrakech, UCA noblesse DieAnderen yahya.elfakir
114 United States University of Illinois at Urbana-Champaign jmseo2 muramasa_912 tsmith13
115 Australia The University of Western Australia
116 China South China Agricultural University
117 Colombia Universidad de los Andes, Colombia
118 India Indian Institute of Technology — Bombay
119 Mexico ITESM Campus Monterrey
120 Russia National University of Science and Technology "MISiS"
121 United States Carleton College
122 United States Harvard University
123 United States Iowa State University
124 United States Messiah College
125 United States Northwestern University
126 United States Princeton University
127 United States Rice University
128 United States University of Wisconsin — Madison

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By ahmed_aly, 9 years ago, In English

Edit: Looks like the following outputs are correct, you can use them to judge your solutions (or you can submit your solutions here). Also it looks like many contestants will fail in the last problem, so I guess the cutoff will be 60 points (anyone with at least 60 points will be qualified).

Until Facebook finishes the manual judging, let's compare our solutions against each other. Here are what I think should be the correct outputs for the given inputs, please run your solutions against these inputs and write a comment here and say what your solution agrees with and what it doesn't.

A. Homework

Full input link: https://drive.google.com/file/d/0ByHbOJKKpXM9dEtiSkxZdExXR00/

Full output link: https://drive.google.com/file/d/0ByHbOJKKpXM9Y1Q0dVZvUkRxanc/

B. Autocomplete

Full input link: https://drive.google.com/file/d/0ByHbOJKKpXM9eklueGpLdmh1ZEE/

Full output link: https://drive.google.com/file/d/0ByHbOJKKpXM9TWdMUVo2amJ2RUk/

C. Winning at Sports

Full input link: https://drive.google.com/file/d/0ByHbOJKKpXM9eTU0YVFRSHUyWTg/

Full output link: https://drive.google.com/file/d/0ByHbOJKKpXM9NnhpX2xfOUlJelU/

D. Corporate Gifting (this is not the output I submitted, what I submitted was wrong)

Full input link: https://drive.google.com/file/d/0ByHbOJKKpXM9elVuOVNld3pRMkE/

Full output link: https://drive.google.com/file/d/0ByHbOJKKpXM9SG43c1R3ZHlrWGc/

The above outputs are not guaranteed to be correct, I'll update the post if I found that any of them is wrong.

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By ahmed_aly, 9 years ago, In English

Hello everyone,

I'd like to invite you to participate in a contest on A2 Online Judge. The contest problems will be from the ACM Egyptian Collegiate Programming Contest 2014 which was held yesterday.

The problems are not available anywhere yet, so it should be original problem set for anyone who didn't attend the contest. The problems difficulty is medium, and it should be a good team practice if you are preparing for an ACM regional contest.

The contest will follow the ACM standard rules and its duration will be 5 hours (the scoreboard will be frozen during the last hour). It will start this Saturday October 11th at 3pm UTC, check here for the exact time for you.

This is the contest page: http://a2oj.com/Contest.jsp?ID=13748

This is the registration page: http://a2oj.com/Register.jsp?ID=13748

Good luck & Have Fun.

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By ahmed_aly, 9 years ago, In English

Since TopCoder forums are not that active anymore, and I think Codeforces forums are more active, I decided to start (or continue) the You know your a TopCoder when ... thread here.

It was one of my favorite threads on TopCoder, and I enjoyed reading almost every response.

Let's continue by adding new interesting responses here!

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By ahmed_aly, 9 years ago, In English

The ACM ICPC 2014 world finals scoreboard will be available here: http://a2oj.com/ICPC.jsp?y=2014

The scoreboard contains many TopCoder and Codeforces handles, and many other useful information, and there is an option to chat with other viewers.

This was last year's scoreboard: http://a2oj.com/ICPC.jsp?y=2013

Special thanks to snarknews for making this list which I'm using. I hope that you will like the scoreboard.

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By ahmed_aly, 10 years ago, In English

Hello everyone,

Thanks to the new Codeforces API, I'm working on some new Codeforces tools in my website.

If you have any suggestions or you need any tool/feature to exist, please post it here and I'll be happy to implement it if it's possible.

Thanks, Ahmed Aly

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By ahmed_aly, 10 years ago, In English

A live scoreboard for the ACM ICPC 2013 world finals will be available here: http://ahmed-aly.com/ICPC.jsp

This is just a sample for how it will look like, I might make some small modifications.

The scoreboard displays many information about each team, like the university, the country, the region, the team name, the members TopCoder handles, the members real names and the coach name. Also you will be able to filter the scoreboard by the region or the country. And the scoreboard highlights the champion for each region and shows some icons for the cup and the medals winners.

Edit 1: I added a chatting widget (you can hide it), and the practice contest scoreboard is available now.

Edit 2: Now you can pin your favorite teams to the top of the scoreboard, and you can hide some columns, and there are some statistics rows in the bottom of the scoreboard.

Edit 3: Here is the final ACM ICPC 2013 world finals scoreboard: http://ahmed-aly.com/ICPC.jsp

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By ahmed_aly, 11 years ago, In English

Hi everyone,

I'm attending the ACM ICPC world finals 2013 in Saint Petersburg, and we are planning to stay for more days after the contest, but we don't have any plans yet. Can you please suggest interesting things/places to do/visit in Russia? Not necessary in Saint Petersburg, we might go to Moscow for example.

Thanks in advance, Ahmed Aly

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By ahmed_aly, 11 years ago, In English

Hello everyone,

I'd like to invite everyone to participate in a 5-hours Gym contest (both teams and individual participants can join) which will be held this Thursday, January 24th at 04:00 PM MSK (GMT+4), check for other time zones here: http://timeanddate.com/worldclock/fixedtime.html?day=24&month=1&year=2013&hour=16&min=0&sec=0&p1=166 (The registration will be opened 6 hours before the contest)

We will use the problems from the last ACM Arab Collegiate Programming Contest 2012 (English statements only), and the actual contest scoreboard will be merged into the Gym's scoreboard. Please don't participate if you already solved or read the problems. Hopefully the problems will be interesting for both Div1 and Div2 coders.

We encourage you to participate in teams to simulate the actual contest.

I'd like to mention that we used Polygon to prepare the problems for the actual contest, which is an amazing system and helped us a lot. Many thanks to Mike Mirzayanov and the whole team.

Edit 1: The registration is opened now, you can register here: http://codeforces.com/gyms

Thanks, Ahmed Aly

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By ahmed_aly, 11 years ago, In English

I'm trying to solve this problem: http://www.codeforces.com/problemset/problem/7/D

And here is my solution: http://www.codeforces.com/contest/7/submission/2865747

My code might look little bit ugly, because I tried to optimize it as much as I can, it's linear solution but it's getting TLE. Why is the time limit so strict like this? Is there any optimizations I can make? I think my solution is the intended solution.

Edit: I got it accepted after pre-computing all the powers instead of using my power function.

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By ahmed_aly, 11 years ago, In English

Something I noticed in many Codeforces contests, the less rated author makes harder problems. Did anyone else notice this?

I think this is because the low rated authors underestimate their problems, and maybe this is happening because they are trying to think like the high rated coders to make sure that the problems are not too easy for them, which makes the problems hard even for the high rated coders.

If you think this is happening, what do you think are the reasons for this?

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By ahmed_aly, 11 years ago, In English

I can't register in this contest.

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By ahmed_aly, 11 years ago, In English

I love any contest with the ACM-ICPC rules, and I'll love it more if it's rated for Div. 1 also. Please make it rated for Div. 1 also.

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By ahmed_aly, 11 years ago, In English

1- 916852: 509
* 67th in Codeforces Round #137 (Div. 2): +139 (from 1553 to 1692)
* 10th in Codeforces Round #138 (Div. 2): +78 (from 1692 to 1770)
* 87th in Codeforces Round #140 (Div. 1): +103 (from 1770 to 1873)

2- MinakoKojima: 500
* 67th in Codeforces Round #138 (Div. 1): +121 (from 1772 to 1893)
* 23rd in Codeforces Round #140 (Div. 1): +129 (from 1893 to 2022)

3- gchebanov: 468
* 25th in Codeforces Round #138 (Div. 1): +105 (from 2009 to 2114)
* 7th in Codeforces Round #140 (Div. 1): +99 (from 2114 to 2213)

4- azizkhan: 459
* 11th in Codeforces Round #138 (Div. 1): +139 (from 1914 to 2053)
* 50th in Codeforces Round #140 (Div. 1): +61 (from 2053 to 2114)

5- bayleef: 422
* 17th in Codeforces Round #138 (Div. 1): +103 (from 2058 to 2161)
* 13th in Codeforces Round #140 (Div. 1): +81 (from 2161 to 2242)

You can check how are the above scores calculated here: http://codeforces.com/blog/entry/5169

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