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athin's blog

By athin, history, 4 years ago, In English,

Err.. I'm sorry for Tebak_Siapa_Aku, the official announcement is late, but here is it, just a couple of minutes after you posted the unofficial here :')

Hello everyone! :D

Indonesia will hold 2016 National Olympiad in Informatics this week (May 16th — May 18th 2015) in Palembang, Indonesia. It is a competition for Indonesian high school students as one of the preliminary round of Indonesian IOI selection. The contest consists of three separated contests:

  • Day 0 (Practice Contest): Monday, May 16th 14.00 — 17.00 (UTC +7)
  • Day 1: Tuesday, May 17th 08.30 — 13.30 (UTC +7)
  • Day 2: Wednesday, May 18th 08.30 — 13.30 (UTC +7)

And this is the second year for Indonesia (last year event : here) to invite everyone around the world to try solving the problems by participating the Open Contest! The Open Contest will be held in https://competition.ia-toki.org/.

There will be three different contests, one for each day. You may participate them separately (e.g. only participate in Day 1 and Day 2, but not in Day 0), but we expect you to join them all. Unlike last year, they are not virtual contests. The Open Contest will start after an hour from the real contest. Here are the schedule and details for the Open Contest:

Several notes:

  • No medals/certificates will be awarded to Open Contest participants.
  • Each contest will have 3 IOI-styled problems.
  • Problem statements will be provided in English and Indonesia.
  • There is a submission limit of 30 for each problem.

We hope you will find many interesting problems here. Good luck and thanks for your participation! :D

UPD Open OSN is delayed for 30 minutes, it will start on 10.00.

UPD Registrations are open until the start of each contests, except for Day 0 (you can register at anytime before the end of the contest).

UPD The results are out! You can access Open OSN results here.

Thanks for all people who participated in this contest! We wish you had a great problemset and experiences, we are looking forward to your participation next year! :D

Indonesian National Olympiad in Informatics Committee

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

Auto comment: topic has been updated by saitammar (previous revision, new revision, compare).

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4 years ago, # |
Rev. 2   Vote: I like it 0 Vote: I do not like it

Can you provide a template code for problem 2 ? I still can't figure out how to interact.

I used while (cin >> n >> m) {} and got AC. But if I use while (scanf("%d%d", &n, &m) == 2) or while (scanf("%d%d", &n, &m) != EOF), I got TLE.

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    4 years ago, # ^ |
      Vote: I like it +5 Vote: I do not like it

    Assuming that you code in C++, here's the template if you're using cin and cout:

    while (cin >> n >> m) // read judge's feedback/input
    {
        // do something ...
        cout << something() << "\n";
        fflush(stdout);  // let the judge read your output
    }
    

    or

    while (cin >> n >> m) // read judge's feedback/input
    {
        // do something ...
        cout << something() << endl;
        // by using endl, you automatically flush your output
    }
    

    or if you're using scanf and printf:

    while (scanf("%d %d", &n, &m) == 2)
    {
        // do something
        printf("...", something());
        fflush(stdout); // let the judge read your output
    }
    
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4 years ago, # |
Rev. 2   Vote: I like it +13 Vote: I do not like it

Just a note for those red coders who are looking for challenge (or maybe IOI warmup) :

This contest is one of the first round in choosing Indonesian IOI 2017 team. We still have like around 90 people and we will choose the medalists (around 30 people) to advance to the next round. Thus, the problems on this contest may not be as challenging as you think. As a comparison, I predict the hardest problem in this contest will not be harder than standard Div 1 C problem. (just a prediction, I am not inside the committee).

We will usually have harder problems for later rounds of selection, but unfortunately we don't normally open those contests for public.

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4 years ago, # |
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Auto comment: topic has been updated by saitammar (previous revision, new revision, compare).

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4 years ago, # |
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Seems like one cannot register after contest starts. Can you please register me? Same handle.

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    4 years ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Unfortunately, the registrations are open until the start of each contests. The only exception is for the Day 0.

    You can still participate on Day 2 afterall :)

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4 years ago, # |
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How to solve the last subtask of the interactive problem?

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    4 years ago, # ^ |
    Rev. 2   Vote: I like it +8 Vote: I do not like it

    I'll post problem description here, so everyone can enjoy this problem :)

    The Problem: Taming a Bomb

    After reading the problem you may play "Taming a Bomb" game manually

    Step by step solution
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4 years ago, # |
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Will the contest allow upsolving ? I tried but after I clicked on Submit, it jump back to the announcement page.

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    4 years ago, # ^ |
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    The contest problems will be added to Training later (after day 2 contest ended). Actually I'm not sure about when the problems will be added there for this kind of contest.

    It will be added to this archive, but not all the problems are provided in English. Currently, the only problemset which have English description is OSN Informatika 2015 (last year National Olympiad in Informatics).

    Good luck for day 2! :)

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4 years ago, # |
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When will you publish the scoreboard? (Both official and open contests)

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    4 years ago, # ^ |
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    The closing for the Olympiad itself will be held two days from now (on Friday). So, I guess the scoreboard will be published not long after the closing has ended...

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      4 years ago, # ^ |
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      Haven't they published the scoreboard yet?

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4 years ago, # |
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The results are out! :D

You can access Open OSN results here.

Thanks for all people who participated in this contest! We wish you had a great problemset and experiences, we are looking forward to your participation next year! :D