aryanv's blog

Iranian Combinatorics Olympiad 2024
By aryanv, history, 4 weeks ago, In English

Hello everyone,

The Iranian Combinatorics Olympiad is back!

For those who are not familiar with this competition, this is an online event which is free to register and participate in. Everyone can participate in this challenge in a team of at most 3! The contest contains two rounds and students will be challenged to solve IMO style combinatorial questions. The nice thing about this contest, is that it is the first contest in the world that has an online judging system for a theoretical exam. The registration is now open!

Anyone in any grade and educational level can participate in this exam.

As I mentioned above, this contest is completely free and we are relying on sponsors to support such an event! To help us grow and make this contest is bigger, the only request that we have from you guys is to:

1) Participate in this event if you are interested in solving these types of problems

2) If it is possible for you, we would be happy if you can send us a short video (to our official email), introducing yourself, your nationality and say "OLAMPIAD TARKIBIAT IRAN" which translates to "Iranian Combinatorics Olympiad". We would like to thank you in advance for your kind support.

The event will be on two days, 31st of October and 1st of November.

official website: https://ico-official.com email: [email protected]

If you have any questions, you can ask under this blog and I will try to answer them as much as possible.

  • Vote: I like it
  • +122
  • Vote: I do not like it

»
4 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Is this like IGO?

→ Reply
  • »
    »
    4 weeks ago, # ^ |
      Vote: I like it +9 Vote: I do not like it

    It will be very similar, however the questions will be combinatorics instead of Geometry. Usually the questions will have higher quality and require more creativity in ICO when compared to IGO.

    → Reply
»
4 weeks ago, # |
  Vote: I like it -16 Vote: I do not like it

Finally! A math contest that I might solve something in!

→ Reply
»
4 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

If a team participates online, do they have to gather in the same place or can they participate from their home?

→ Reply
  • »
    »
    4 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    There is no need to gatherin the sane place! They can participate from their home

    → Reply
»
4 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

I see how 2020 had a "short answer exam" and "main exam", while 2021 had round 1 and round 2 (this is based on the info from archive). Will a similar system be adopted this year?

→ Reply
  • »
    »
    4 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Yes there will be the similar system. First round will be a "Short answer exam" and the second round will be "Long proof questions".

    → Reply
»
4 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

How many problems are there? Since I looked at the booklet and there were more than 20 I'm guessing that's the shortlist. How are answers sent? as a number or with proof? And is it all day or we can choose the hour? What hour will it be?

→ Reply
  • »
    »
    4 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    There will be 15 questions in the short answer part and you will have 2 hours to solve them. There will be 7 questions on the long answer part and you will have 5 hours to solve them.

    The exam will be:

    31th of October — The exam will start at 8:30 am (EST) or 4:00 pm (Iran's local time) 1st of November — The exam will start at 6:30 am (EST) or 2:00 pm (Iran's local time)

    → Reply
    • »
      »
      »
      4 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      How many tries do we get in the short answer first round? Do we get less points if we get it wrong?

      → Reply
      • »
        »
        »
        »
        4 weeks ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        You won't notice if it is wrong! The live judging system is only for the long answer part! In the short answer part if you are wrong then you will find out at the end of the exam! There is no negative marks for answering the questions wrong. However, the teams with the same score will be ranked based on the number of incorrect answers (lesser the better) to qualify for the Long answer part

        → Reply
        • »
          »
          »
          »
          »
          4 weeks ago, # ^ |
            Vote: I like it 0 Vote: I do not like it

          How do you decide who advances to round 2?

          → Reply
          • »
            »
            »
            »
            »
            »
            4 weeks ago, # ^ |
              Vote: I like it 0 Vote: I do not like it

            In the elementary level there is no round 2. In the advanced level the top 30 teams from the first round and in the level "Free" the top 20 teams will be qualified to participate in the second round. There are some additional rules based on the country you are participating from as well. (Only top 2 teams of every country can reach the final round)

            → Reply
            • »
              »
              »
              »
              »
              »
              »
              4 weeks ago, # ^ |
                Vote: I like it 0 Vote: I do not like it

              Are elementary and advanced the same questions?

              → Reply
            • »
              »
              »
              »
              »
              »
              »
              4 weeks ago, # ^ |
                Vote: I like it 0 Vote: I do not like it

              My team (all in grade 9 or below) is registered for the ICO. Will we be in the elementary or advanced category?

              → Reply
              • »
                »
                »
                »
                »
                »
                »
                »
                4 weeks ago, # ^ |
                  Vote: I like it 0 Vote: I do not like it

                Elementary

                → Reply
                • »
                  »
                  »
                  »
                  »
                  »
                  »
                  »
                  »
                  4 weeks ago, # ^ |
                    Vote: I like it 0 Vote: I do not like it

                  Thanks.How many rounds are there in the Elementary category, and how many questions are in each round?

                  → Reply
                • »
                  »
                  »
                  »
                  »
                  »
                  »
                  »
                  »
                  4 weeks ago, # ^ |
                    Vote: I like it 0 Vote: I do not like it

                  1 round, 15 questions

                  → Reply
                • »
                  »
                  »
                  »
                  »
                  »
                  »
                  »
                  »
                  4 weeks ago, # ^ |
                    Vote: I like it 0 Vote: I do not like it

                  What is the date and time (IST) of the Round 1 exam for the Elementary category?

                  → Reply
»
4 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Hi, I'm interested in participating in this contest. Had a great experience in the 2021 edition.

Just want to check what time the contest is being held. I can't find this info. Also are non-students allowed to participate? What should I put for the "school name" in the registration form?

→ Reply
  • »
    »
    4 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Hi, we are glad to hear that! Of course! The level "Free" is exactly designed for people who are students in University of not students at all. If you are not a student just fill in N/A as your "school name".

    The time of the exam is:

    31th of October — The exam will start at 8:30 am (EST) or 4:00 pm (Iran's local time)

    1st of November — The exam will start at 6:30 am (EST) or 2:00 pm (Iran's local time)

    → Reply
»
4 weeks ago, # |
  Vote: I like it +1 Vote: I do not like it

I would like to generally add that if you would like to participate in the exam. IT WOULD BE A VERY VERY BIG SUPPORT TO US TO SEND THE VIDEO I explained in my blog. That is a significant help for us to find sponsors and keep the exam free of any charge.

→ Reply
»
4 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Is it open book?

→ Reply
  • »
    »
    4 weeks ago, # ^ |
      Vote: I like it +18 Vote: I do not like it

    yup! You are allowed to use any materials inside any book or internet (as long as it is written before the starting time of the contest)

    → Reply
»
4 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

I have tried to register from Bangladesh several times, but every time a server issue occurred.

When I tried for the 1st time, the server issue "Oops...." occurred. I tried several times again, but each time, it showed, "All the emails and phone numbers have already been taken." I tried to log in with the same information, but it still didn't work. My teammate also tried to register from a different device but, he faced the same problem.

What should I do?

→ Reply
  • »
    »
    4 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Hi Try again! The problem should be solved

    → Reply
    • »
      »
      »
      4 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      We tried again but, the issue was not solved. It shows the same massage.

      → Reply
»
4 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

What is the deadline for registring for the competition? Also, will we need to join a zoom meeting or something like that for supervising?

→ Reply
  • »
    »
    4 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    26th of October! No the exam won't have any kind of supervising! Notice that the exam is open book and you are allowed to use your coding skills for the Short answer questions if you found it helpful

    → Reply
»
4 weeks ago, # |
  Vote: I like it +1 Vote: I do not like it

In the PDFs on the official website, under the archive for previous contests, I only see numeric answers for the first section. Are there solution explanations for these problems?

→ Reply
  • »
    »
    4 weeks ago, # ^ |
      Vote: I like it +3 Vote: I do not like it

    Unfortunately I believe that the explained solution does not exists for these problems and only the numeric answer is available at the current moment.

    → Reply
»
4 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

How to pronounce olampiad tarkibiat iran?

→ Reply
  • »
    »
    4 weeks ago, # ^ |
    ← Rev. 2   Vote: I like it 0 Vote: I do not like it

    Exactly how it is written! "OLAMPIAD TARKIIBIIAT IRAN" Thank you so much. Notice the two "II" is exactly pronounced like the two "ee" in the word "Teeth"

    → Reply
»
4 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Should all team members join the contest to submit the answers or any one from the team should submit?

→ Reply
  • »
    »
    4 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Anyone from the team can submit the answers!

    → Reply
»
4 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

It is possible to allow password change of the team account?

→ Reply
»
3 weeks ago, # |
  Vote: I like it +6 Vote: I do not like it

is the registration over?

→ Reply
»
3 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

When I registred my team, I selected that we were in 9th grade or below (as we were), but can we participate in the advanced category? Also, do I have to write an email about this request or can we just select the category during the contest?

→ Reply
  • »
    »
    3 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    As far as I am aware, this is not possible! but try your luck by sending them an email!

    → Reply
»
3 weeks ago, # |
← Rev. 2   Vote: I like it 0 Vote: I do not like it

To all who have registered the online event!

You can follow the official news from the following Telegram Channel: https://t.me/ICOofficial

The first round will start tomorrow (October 31st) at 4:00 pm (Iran's standard time) which is equivalent to 8:30 am (EST)

→ Reply
»
3 weeks ago, # |
← Rev. 4   Vote: I like it +5 Vote: I do not like it

Hello. My website says 23 mins till contest starts even thought it should be 3 mins. Please help.aryanv

→ Reply
  • »
    »
    3 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    I assume youre participating in the free-level. We have the same problem.

    → Reply
»
3 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

This is a bit late but our team should be in advanced but the website put is into the free level for the first round. Is there a way to fix this for the second round to be in the advanced section? aryanv

→ Reply
»
3 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Does the official website have English statements ? I just can see the Iranian version for the problems

→ Reply
»
3 weeks ago, # |
  Vote: I like it +8 Vote: I do not like it

When will results be published?

→ Reply
  • »
    »
    3 weeks ago, # ^ |
      Vote: I like it +8 Vote: I do not like it

    also the expected answers?

    → Reply
    • »
      »
      »
      3 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it
      Our answers:
      → Reply
  • »
    »
    3 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    The final results should be published in about 2 hours! (8:00 PM Iran's Standard Time)

    → Reply
»
3 weeks ago, # |
← Rev. 6   Vote: I like it 0 Vote: I do not like it

Here are the answers for my team (advanced/free) if anyone wants. We think Q2 is wrong, the answer can be 3,4,5. Below are the constructions:

constructions for q2

Also, we thought the exam will end 20 minutes later since it started 20 minutes later so we didn't upload some our answers for like 4 problems (including Q2)....

answers
→ Reply
  • »
    »
    3 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    for 15, how do you solve in 39+eps moves a graph which is like a star, but every edge is a 49-node chain?

    → Reply
  • »
    »
    3 weeks ago, # ^ |
    ← Rev. 2   Vote: I like it 0 Vote: I do not like it

    isnt P11 supposed to be 10?

    → Reply
    • »
      »
      »
      3 weeks ago, # ^ |
      ← Rev. 2   Vote: I like it 0 Vote: I do not like it

      yea we screwed up for that one, I just checked again answer is 10

      → Reply
      • »
        »
        »
        »
        3 weeks ago, # ^ |
          Vote: I like it +5 Vote: I do not like it

        The statement says that rotations aren't considered different so it should be 1.

        → Reply
  • »
    »
    3 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Could you share the solutions in detail for P3 and P11. I got (20C10)² for P3 and 1 for P11.

    → Reply
    • »
      »
      »
      3 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      Sharing constructions for P11 (if you have greater than or equal 2) would be appreciated as well

      → Reply
    • »
      »
      »
      3 weeks ago, # ^ |
        Vote: I like it +3 Vote: I do not like it

      I ran a script for P11 and I think it's 1.

      → Reply
  • »
    »
    7 days ago, # ^ |
    ← Rev. 3   Vote: I like it 0 Vote: I do not like it

    What is the construction for 14? I can only archive 150.

    UPD: Already found the construction for 199.

    → Reply
»
3 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Just to let you all know if you didn’t check already that the results are out in the telegram channel!

→ Reply
  • »
    »
    3 weeks ago, # ^ |
    ← Rev. 2   Vote: I like it 0 Vote: I do not like it

    Hi, is there an official answer key, I would be interested in knowing the answers for problems 2 and 5 for the free division

    → Reply
    • »
      »
      »
      3 weeks ago, # ^ |
      ← Rev. 2   Vote: I like it 0 Vote: I do not like it

      How is p2 not bonus man? (I think the answer should be 3, but there are constructions for 5, 7 as well) So give all three or bonus. How is 3 wrong :(

      → Reply
    • »
      »
      »
      3 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      The official answers should be published in the up coming days! The reason for the delay is the offline competition!

      → Reply
»
3 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Hello! If we won elementary division, can we also participate for the second advanced round? We want to see how good we will do. Who should we talk to? Thank you!

→ Reply
  • »
    »
    3 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    First of all congratulations for winning the elementary contest! I mentioned this in our meeting with the Executive Committee but unfortunately it got rejected in the voting since it is against the law which was originally announced! Sorry there is nothing beyond this that I can do, I tried my best to let you in!

    Although we encourage you to try the questions yourself on your own and challenge yourself

    → Reply
    • »
      »
      »
      3 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      Thank you!

      → Reply
    • »
      »
      »
      3 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      Is there any way to compete unofficially?

      → Reply
      • »
        »
        »
        »
        3 weeks ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        No, since the competition is based on judging the problems online, we need to use all our human power for the official teams! Maybe what you can do is to write down your solutions and email them to us at the end of the contest, I don’t make any promises but maybe we could mark them for you!

        → Reply
»
3 weeks ago, # |
  Vote: I like it +8 Vote: I do not like it

Where and when will the results be published?

→ Reply
  • »
    »
    3 weeks ago, # ^ |
      Vote: I like it +8 Vote: I do not like it

    The results is already published! Check out the telegram channel! You can find the link in one of my commmets above!

    → Reply
  • »
    »
    3 weeks ago, # ^ |
      Vote: I like it +8 Vote: I do not like it

    Also please accept my congratulations! Your team ranked 3rd (not only in Advanced level but Advanced + Free) and successfully qualified for tomorrow’s competition

    → Reply
»
3 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

hi, I am a member of the team that participated in the Iranian Combinatorics Olympiad 2024 . However, somehow our team's result is not in the overall ranking results you posted and Can you tell us the reason for this?

→ Reply
  • »
    »
    3 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Lot of people with this problem it seems (some of my friends too) which category did you do?

    → Reply
»
3 weeks ago, # |
← Rev. 3   Vote: I like it 0 Vote: I do not like it

How can I know that do I achieve any official award or not?

→ Reply
»
3 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

How are we expected to answer the questions tomorrow

→ Reply
  • »
    »
    3 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    You can either write down your solutions by hand and submit it by scanning using CamScanner or you can submit a Latex file if you prefer, Your solutions must be written in English (or Persian)

    → Reply
    • »
      »
      »
      3 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      I mean, I don't really know how to write solutions since I've never been in a math contest. Can you provide answers to previous ICO for example to get an idea of it?

      → Reply
      • »
        »
        »
        »
        3 weeks ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        OH, that will make your life a bit tough in this contest if you ask my personal opinion! I am not sure if an official solutions exists on the website (or even exists at all or not) but what I can refer you to is the IMO solutions, you can take a look at them, it should be roughly in the same format.

        → Reply
        • »
          »
          »
          »
          »
          3 weeks ago, # ^ |
            Vote: I like it 0 Vote: I do not like it

          I will check them out. Thank you!

          → Reply
»
3 weeks ago, # |
  Vote: I like it +5 Vote: I do not like it

How to do problem 7?

spoiler
→ Reply
»
3 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

aryanv when will the solutions be uploaded ?

→ Reply
  • »
    »
    3 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Probably after a week or so the executive committee must upload the official solutions but the exact date is known to me for now!

    → Reply
    • »
      »
      »
      3 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      Would the final standings be announced along with this? Also is there any scoreboard that has the merged scores?

      → Reply
      • »
        »
        »
        »
        2 weeks ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        I think in the Telegram channels they announced that final results will be available until the end of this Week!

        → Reply
»
2 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Hello! We are Team Cercetasii. We saw the scoreboard and we got 52.07, but adding up all the 7 individual scores, we get a total of 52.09. What shoud we do?

→ Reply
»
7 days ago, # |
  Vote: I like it 0 Vote: I do not like it

Can the final results+medal cutoffs be shared here.. there was a post about the closing ceremony being broadcast online(telegram group message was in Persian and I put it through Google translate so may be inaccurate), if such a broadcast is there could a link below shared?

→ Reply
»
7 days ago, # |
  Vote: I like it +1 Vote: I do not like it

Where Can I find Free and Advanced Level Day2 problems?

→ Reply