### kostka's blog

By kostka, 12 months ago,

In Poland, we have an annual contest with three stages (first online, second and third onsite). During the first stage, we also have a test checking language proficiency (C++ or Python) and the ability to solve algorithmic puzzles. During the final stage, top X contestants are selected to attend the preparation camp and the EJOI.

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 » 12 months ago, # | ← Rev. 2 →   +10 There are no official Junior olympiads in Ukraine. Participants from grade 8 or less have to compete with people from 9th grade. However, there is unofficial Olympiad to choose 4 people for EJOI and EGOI. There are 3 stages during the school year (Online). Top 10 of each contest is invited for finals (Onsite). Finals are held in 2 days with 4 problems each and top 12 are invited to series of contests (from 4 to 6, onsite) to determine top 4 for EJOI/EGOI.
•  » » 12 months ago, # ^ |   0 Oh, I forgot to write that based on the results of ROI, selection for IOI takes place
 » 12 months ago, # | ← Rev. 2 →   +52 Korean olympiad has three divisions for each school class: Elementary (grade 1-6), Middle (grade 7-9), High (grade 10-12). Each division has a different problem set (but possibly with shared problems), but their contest rules are identical. I think ainta won the elementary division in 2009.This is the hardest problem from the elementary division contest of 2019 KOI. (People rated it as the hardest problem ever posed in that division.) Can you beat the grade 6 schooler?There are $N$ robots in a cycle of length $M$. Each robot's position in the cycle are given as an integer $0 \le x_1, x_2, \ldots, x_N \le M-1$.A position in a cycle can be monitored by a robot if their shortest distance is at most $R$ (In other words robot can monitor a cyclic interval of length $2R$ centered of its position).We want to monitor all parts of the cycle. For this, we can move the robots. Can you find the minimum value $X$ such that you can move robot's position by at most $X$ so that all parts of the cycle can be monitored? It is guaranteed that $M \le 2RN$, therefore the solution always exists. $N \le 10^6, M, R \le 10^9$https://www.acmicpc.net/problem/17617IOI selection camp is open for grade 8-11 and it is completely independent of the national olympiad.
•  » » 12 months ago, # ^ |   0 In that problem, is X the bound on the sum or the maximum of robots movements?
•  » » » 12 months ago, # ^ |   0 Maximum
•  » » 11 months ago, # ^ |   +10 I won in 2010. Don't make me feel old :(
•  » » 10 months ago, # ^ | ← Rev. 2 →   0 this problem is quite insane too. 2006 KOI Elementary division - problem 3https://www.acmicpc.net/problem/2574use translator I'm too lazy to translate it into English by myself xd
 » 12 months ago, # |   0 in Russia people are invited for ejoi capms if they are a prize winners in ROI
 » 12 months ago, # | ← Rev. 3 →   0 So in Russia the only junior olympiad is Keldysh (and also Moscow Olympiad in 7-8 group, maybe). But the results don't really matter on choosing EJOI team (it just counts as regular qualification contest, so I failed all contests and done well on Keldysh, but didn't pass to EJOI). It's easy to get to the final of olympiad and there's a lot of diplomas given. But the last problems are usually hard enough (for example, this year's 2 last problems have difficulties of 2500 and 2600 on codeforces, and even more for 2019 and 2020). Before the olympiad there's usually junior camp in Sirius (for participants, who are not prize-winners on ROI), and it helps begginers very much. I've participated twice, once with junior camp before the olympiad and once as an EJOI candidate, and both times it was interesting and useful for me.Rounds based on Keldysh olympiad — 2019, 2020, 2021
 » 12 months ago, # |   +298 In my country it's very badly organized, problems are boring and everything could be done a way better. If you want to know more details, I think that kostka is one of the organizers, you can ask him.
•  » » 12 months ago, # ^ |   -111 kostka is the author of the blog lol.
•  » » 12 months ago, # ^ |   +43 Don't even mention the old organizers...
•  » » 12 months ago, # ^ |   +78 Especially when people like Radewoosh are setting problems. Disgusting.
 » 12 months ago, # |   +29 In India, there are two olympiads for the first stage, ZIO(Zonal Informatics Olympiad) and ZCO(Zonal Computing Olympiad) Qualifying any one suffices for passing to the national stage INOI. Juniors(grade 8 or less) participate in the same ZIO and ZCO like every senior grade, but the cutoffs are lower for them. In INOI(Indian National OI), cutoffs are the same for everyone. As an example,in 2021,cutoffs for ZCO:Males: Class XII: Everyone with a total score of >= 94/200 will qualify for INOI Class XI: >= 83/200 Class X: >= 72/200 Class IX: >= 65/200 Class VIII: >= 49/200 Class VII and lower: >= 34/200Females: Class XII: Everyone with a total score of >= 87/200 will qualify for INOI Class XI: >= 54/200 Class X: >= 48/200 Class IX: >= 43/200 Class VIII: >= 28/200 Class VII and lower: >= 22/200
•  » » 12 months ago, # ^ |   -37 Different cut off marks for male and female. Such a nice idea!!!
•  » » 12 months ago, # ^ |   0 Small correction: In INOI the cutoff for medals is the same for everyone but the cutoff for TC may be different for different grades.
 » 12 months ago, # |   +1 Holly molly that's very well organized! In my country, we don't even have a preparation camp we just have a few classes a week before ejoi in which you enter if you were top X on Junior Serbian Informatics Olympiad. Also, last year, JSIO was extended for 10 minutes 2 times because of bad problems and too many equal results. It's funny, in that 20 minutes, some people got more points by printing random numbers (you could see the correctness on every test case and there wasn't any partial score so you would get a point for every accepted test). Due to all these circumstances, I did not make it to the EJOI last year. This year the commission has changed so probably the organization will be better.
 » 12 months ago, # |   +113 In China, grade 8 is old enough to reach LGM.
 » 12 months ago, # |   -12 When I was in the eighth grade, I am pretty sure that even HTML and MS Paint Animations seemed like magic to most of my class [me included]. So even if these things do exist, the awareness levels are super low in my country.
•  » » 12 months ago, # ^ |   0 Before the introduction of programming, the subject "computer" is basically a really really slow tutorial on how to use a computer and basic things like how to open ms paint or make text bold in wordpad, informative for people who don't have access to computers but for a lot of people(or atleast for me) it is a painfully slow journey through the obvious.So yeah, i agree, would be very suprised if anyone knew about cp or anything like this on cf.
 » 12 months ago, # | ← Rev. 2 →   0 In romania, it is generally this way: You go to county-level, pray you don't get huge numbers or something unbearable to write You go to national-level, pray you don't have to parse time expressions You go to TSTs, hope (for nothing) you don't get the ones listed earlier, along with triple lookup table optimizations for combinatorics problems, and tests that aren't tailored to whatever the author's solution was. Oh, and also pray you have some feedbackThen, when you're not a junior anymore, all you have to do is just pray for the lack of """mathematical""" puzzles, the rest will automagically disappear (because there will always be someone who can do the rest and you really can't blame the problem setters for your own incapability, can you?)
 » 12 months ago, # | ← Rev. 2 →   0 In Spain, we have an online contest to qualify to the final and there are also regionals contest, then we have an onsite final as you can expect. One interesting fact is that harbour.space is giving free classes to all students and since then the level has been rising a lot year after year.
 » 12 months ago, # |   0 In Iran we just have Olympiads for mathematics and combinatorics and science in junior school :/ we don't have any Olympiad related to computer in grades lower than 10 :(