PieArmy's blog

EJOI 2025 Teams
By PieArmy, history, 12 months ago, In English

Recently Türkiye's team selection for EJOI has ended and I love EJOI so I thought why not make the EJOI teams blog of this year?

9th edition of EJOI will be held in Bulgaria, Shumen from August 29 to September 4, 2025. Official website has been announced.

LIVE RANKINGS: results.ejoi.org

Result of both days combined: results.ejoi.org/standing/Day1,Day2

USERNAME: results

NEW PASSWORD: results

You can check the results of the previous EJOIs in this site.

Here is the Türkiye team and their codeforces handles:

  • Efe Gürkaş(EfeG)—1st time at EJOI, 0 attempts left

  • Osman Eymen Karaoğulları(osmiyum)—1st time at EJOI, 1 attempts left

  • Onur Ocak(theheatcoder)—1st time at EJOI, 0 attempts left

  • Yiğit Yenmez(yigit11)—1st time at EJOI, 0 attempts left

If you let me know your country's team, feel free to comment it with the same format and I will add it to the table!

Country Members Average of Max Ratings
Ukraine farkon00 TheFuturoma Kuzma_A Dalvislav56 2069,67
Poland tapikpsp1 Zbyszek99 Filip1221 ArturSmolenski 2026,25
Romania andrei_n HoriaB trraian iordache_ 1968,5
Kazakhstan Abilmansur-007 isagi_yaichki Arkanefury Dibamboo 1894
Bulgaria kchu_z GeneralRtivity BFC_BAB BauBauDani 1684
Türkiye EfeG osmiyum theheatcoder yigit11 1683,75
Georgia materekh saba_goduadze giorgi123glm Sandropeikrishvili 1667,5
Serbia stanirina mihajlo0404 LazaPro veljathecuber 1644,75
Croatia bornag gkosthefinalboss7 Plavac52431 Vili1234 1588,5
Azerbaijan Ekber_Ekber AtillaMA tooourist AzeTurk810 1535,25
Armenia mamikonm1 HaykManukyan777 labaratory Vache.Kocharyan2012 1515
Macedonia VladiG mkkkkkkkk ZoranIlijoski JakovG 1431,75
Cyprus alexistsa Antziapo mariza_CY charalambides.a1810 1424,34
Kyrgyzstan PokemonMaster emirhanbanan aktan4ik baymyrzaevaruubek10 1412,5
Bulgaria 2 Damyan_DD nikolamanolov m.viss2010 aleksey.kartashev1 1385,34
Saudi Arabia sth6 Hashim_Bas Eyadooz1 AhmadAlhussain 1368,75
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12 months ago, hide # |
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About yigit11, we both got the same score, the national committee should favor the young ones (I'm technically not 12 yet, still have 5 days to turn 12 :D) to encourage future pursuits, or at least as a birthday gift IMO :D (just kidding)

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12 months ago, hide # |
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    12 months ago, hide # ^ |
     
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    They announced it during the closing ceremony of EJOI 2024.

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      12 months ago, hide # ^ |
       
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      They told us at the national competition that Azerbaijan cancelled and EJOI is being held in Kazakhstan instead

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        12 months ago, hide # ^ |
         
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        Alright then I will update it when it is announced officially, thank you! Izho is a really good olympiad so I am looking forward for EJOI 2025!

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        12 months ago, hide # ^ |
         
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        Are you sure that it will be in Kazakhstan? Last I heard they were considering it but didn't know if they had enough money?

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          12 months ago, hide # ^ |
           
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          Our country's team leader said it's in Kazakhstan, we didn't get any news on the location changing since. I mean, I can't go to EJOI anymore but I know people who are going to the team selection next week

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          12 months ago, hide # ^ |
           
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          Bro will you be a team leader?

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Macedonia:

-Vladimir Grchev VladiG (0 tries left)

-Marko Krenkov mkkkkkkkk (0 tries left)

-Zoran Ilijoski ZoranIlijoski (1 try left)

Same as last year, currently there is no confirmed 4th team member, I will reply to this comment if there are any updates.

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12 months ago, hide # |
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    12 months ago, hide # ^ |
     
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    No but I am gonna ask a friend who will be competing to let me know when our national comittee tells them.

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Poland team on oij.edu.pl

SzymonKrzywda

Zbyszek99 <- gold on BOI

Filip1221

ArturSmolenski <- Bronze on BOI and he is in the polish representation for IOI

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12 months ago, hide # |
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I had a wrong strategy on day 1 so i got a bad result... Btw,in the winter camp of Türkiye, I was the one of two guys who have two more attemps for the national team selection with onepersonintheuniverse .Can somebody tell me that how big is my advantage on national team selections in next years?

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    12 months ago, hide # ^ |
     
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    In my opinion it is very doable for you if you study well and dont slow down. meLearnCode met olympiad when he had only one year left for EJOI and he got in the team that year. Also all the people currently in the team will be gone in your last year.

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      12 months ago, hide # ^ |
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      Thanks for support and I wanna ask another question.It looks like that if you are in the national team,you are guaranteed to be in the summer camp next year, if it is true is it also works for 9th graders (which is going to high school contest next year) i dunno it so can someone please answer this too, I'm all ears :p

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Vote: I like it +7 Vote: I do not like it

EJOI will be held in Shumen, Bulgaria from August 29 to September 4 (An official invitation has been sent, I think)

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EJOI site: https://2025.ejoi.org/

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Azerbaijan:

Əkbər Əhmədov(Ekber_Ekber) — 1st time at EJOI, 0 attempts left

Atilla Mustafa(_atilla_) — 1st time at EJOI, 0 attempts left

Ömər Əliməmmədzadə(tooourist) — 1st time at EJOI, 0 attempts left

4th participant will be determined after APIO

UPD: 4th participant from Azerbaijan was finally selected:

Fateh Əhmədzadə(AzeTurk810) — 1st time at EJOI, 0 attemps left

Good luck to everyone participating at EJOI2025!

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Vote: I like it +36 Vote: I do not like it

Here is the Georgian team:

  • Mate Rekhviashvili (materekh) — 4th time at EJOI (WOW), 0 attempts left

  • Saba Goduadze (saba_goduadze) — 1st time at EJOI, 0 attempts left

  • Giorgi Maisuradze (giorgi123glm) — 1st time at EJOI, 0 attempts left

  • Aleksandre Peikrishvili (Sandropeikrishvili) — 1st time at EJOI, 0 attempts left

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Vote: I like it +15 Vote: I do not like it

Croatia:

  • Borna Gudac bornag (2nd time, 0 attempts left)

  • Gabriel Kos gkos (1st time, 1 attempt left)

  • Gita Radiković Plavac52431 (1st time, 1 attempt left)

  • Ozren Vili Paunović Vili1234 (1st time, 0 attempts left)

I wish everyone good luck!

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Ekber_Ekber will win EJOI 2025! I am proud of having such a classmate!

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dssfsuper2 will win EJOI 2025 !

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Cyprus:

  • Alexis Tsaggaris (alexistsa) — 2nd time at EJOI, 1 attempt left
  • Antreas Tziapouras (Antziapo) — 2nd time at EJOI, 0 attempts left
  • Andreas Charalambides (charalambides.a1810) — 1st time at EJOI, 1 attempt left
  • Mariza Paspalli (mariza_CY) — 3rd time at EJOI, 0 attempts left
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Vote: I like it +4 Vote: I do not like it

Ekber_Ekber and tooourist will win EJOI 2025!

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Vote: I like it +26 Vote: I do not like it

materekh will win EJOI 2025!

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yigit11 Our newbie gigachad

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Ukraine

-Vladyslav Khalin farkon00

-Roman Sadovnikov TheFuturoma

-Andrii Kuzma Kuzma_A

-Vladyslav Vynnyk vValsi

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The last person for ejoi Azerbaijan team is AzeTurk810

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AzeTurk810 will win EJOI 2025!He really struggled to take part in this competition.

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I can bet with anyone that ArturSmolenski will be in top 3 in this ejoi

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Vote: I like it +23 Vote: I do not like it

Romanian junior selections ended today, here is our team for EJOI:

Andrei Nemțișor (andrei_n) — 1st time at EJOI, 1 attempt left

Horia-Andrei Boeriu (HoriaB) — 1st time at EJOI, no attempts left

Traian Mihai Danciu (trraian) — 1st time at EJOI, 2 attempts left

Matei Ștefan Iordache (iordache_) — 1st time at EJOI, no attempts left

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10 months ago, hide # |
 
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Armenia Team:

  1. Mamikon Hambaryan mamikonm1 1st time 1 left

  2. Hayk Manukyan HMan26 1st time 0 left

  3. Aren Grigoryan labaratory 2nd time 0 left

  4. Vache Kocharyan BetaZero 1st time 2 left

places in list matches plases in team selection test places

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Bulgarian first team:

No more attempts left for all of them. (They dont look very strong but dont underestimate them. They are at least very cute <3)

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    10 months ago, hide # ^ |
     
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    Why are they all unrated :(

    Is it because their average this way is $$$\frac{0}{0} = infinite$$$?

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Vote: I like it +8 Vote: I do not like it

Serbia:

  • Irina Stanišić stanirina (3rd time, 0 tries left)
  • Mihajlo Janičić mihajlo0404 (1st time, 0 tries left)
  • Lazar Nikić LazaPro (1st time, 0 tries left)
  • Veljko Vitkovac veljathecuber (1st time, 0 tries left)
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Saudi's team:

Fares Alraddadi (STH6) — 1st time at EJOI, no attempts left

Hashim Basuni (Hashim_Bas) — 1st time at EJOI, no attempts left

Eyad Alkhalifa (Eyadooz1) — 1st time at EJOI, 1 attempt left

Ahmad Alhussain (Kokobird1) — 1st time at EJOI, no attempts left

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Kazakhstan:

Abilmansur Kurmet(Abilmansur-007) — 1st time at EJOI, 0 attempts left

Nurali Shaimerden(QazLon) — 1st time at EJOI, 0 attempts left

Sayat Yussupov(Arkanefury) — 1st time at EJOI, 0 attempts left

Dinmukhammed Mugzhan(Dibamboo) — 1st time at EJOI, 0 attempts left

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9 months ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

mamikonm1 will win EJOI 2025

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9 months ago, hide # |
 
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Bulgaria second team: 1. Damyan Svobodnikov Damyan_DD 2. Nikola Manolov nikolamanolov 3. Martin Vissoultchev m.viss2010 4. Aleksey Kartashev aleksey.kartashev1

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9 months ago, hide # |
 
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go france!

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9 months ago, hide # |
 
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this table needs an update.

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8 months ago, hide # |
 
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bornag will win EJOI 2025! I am proud of having such a friend!

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I made my final update before the contest. Good luck to all participants!

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If anyone finds the contest rankings link please send it here

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Day 1's over successfully.

3 of Azerbaijan's participants are in bronze

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8 months ago, hide # |
 
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When will the problems be uploaded?

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7 months ago, hide # |
 
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Cool. but 3 out of 4 Azerbaijani team cheated in past contests on CF? Absurd.

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Do you have results for todays contest

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7 months ago, hide # |
 
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Auto comment: topic has been updated by PieArmy (previous revision, new revision, compare).

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Contest is over congratulations to all participants!

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Is there any judge where I can submit?

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7 months ago, hide # |
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I went through 45 full submissions for the task Reactions and noticed an interesting pattern.

  • Three codes all use the same PBDS trick: store pref[i]-T[i], then query with size - order_of_key(threshold). This is almost a copy of the editorial template.
  • Some other accepted solutions also use PBDS, but in very different ways (pairs with indices, sign inversions, insert+erase, global fill+deletions). Many others use Fenwick trees or segment trees. So they look independent.

Numbers:
- 3 suspicious
- 42 non-suspicious (14 BIT, 12 segtree, 8 PBDS with variations, 3 merge sort tree, 5 hybrids).

I’m curious what others think: is it fair to flag as “editorial copies”, or is this similarity still within the bounds of normal contest coding style?

https://infos.infosbg.com/home?lang=en — source

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    7 months ago, hide # ^ |
     
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    How can I see the submissions?

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      Here

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        Hi, I have reviewed the 3 files side by side. To me, this does in NO way constitute evidence for cheating. The fact that 3 members of the same team used a similar trick to solve the problem simply shows that it's likely they have encountered a similar trick in their training programme, or similar. Please note that they also have vastly different coding styles, and that this is a proctored competition, which means that any form of copying is incredibly unlikely.

        For the benefit of others, I attach a screenshot containing the submissions in question.

        https://postimg.cc/tY88tx5f

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          7 months ago, hide # ^ |
           
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          I agree that direct copying during a proctored contest is unlikely. However, the concern here is not about live copying, but about the possibility of prior hints or guidance.

          What makes these three submissions unusual is that they all rely on the same PBDS idiom (size() - order_of_key(...)) in almost identical form. Among 40+ full solutions, including many that also used PBDS, Fenwick trees, or segment trees, we see a wide diversity of implementations — but no other case of this exact minimalistic trick.

          This statistical anomaly suggests that the similarity is not just due to "common training," and it deserves a more careful look beyond coding style and proctoring

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7 months ago, hide # |
 
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where can i do upsolve?

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7 months ago, hide # |
 
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The upsolve is available at Eolymp.

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