Fefer_Ivan's blog

By Fefer_Ivan, 7 years ago, translation, In English

Hello, Codeforces.

UPD: Round is finished. Thank you for your participation. Final results.

Today (16:00 UTC) we want you to take part in testing and unrated round with unussual scoring system. With your help we want to test new scoring, new type of problems and Codeforces system inside <iframe> tag.

Start time is 16:00 UTC

Go to the Contest!

There are two types of problems: logic puzzles and programming tasks.

A logic puzzle is a task that is designed to be solved by hand (but it is not forbidden to write some helper code to do this). Each logic puzzle consists of one or more tests. Each question can be answered separately from the others. There is a "Submit" button below each test. To answer the question, press "Submit" button. Your answer will be acknowledged and checked after the end of the contest. You can change your answer any number of times – only the last attempt is checked. For the correct answer to the question you will get the number of points which is indicated in the question description.

A programming task is want you can ussually see in Codeforces rounds. Solutions can be submitted at any time during the contest. A solution is evaluated on a fixed set of tests right after it is submitted. For each passed test, a contestant will get a fixed amount of points. The sum of points for all passed tests is the total points received by the solution. The contestant can submit a solution several times. The contestant will receive points for only one solution per problem. The solution with the maximum amount of points will be chosen.

The contest period is divided into two sections: Normal Time (NT) and Extra Time (ET). Each contestant is in only one of these at a time, but which one you're in can vary per contestant. In other words, when one contestant is in Normal Time, another one could be in Extra Time.

  • Normal Time lasts for at most 30 minutes starting from when you click the button "Start Contest". (It could be less than 30 minutes if you start the contest less than 30 minutes before it ends). Points gained in Normal Time are the main way of deciding who wins. A participant with more points gained in Normal Time will always have a better ranking than a participant gaining fewer points in Normal Time.

  • After Normal Time ends you can still solve problems until the contest ends. This period is called Extra Time, and points gained in Extra Time are the second way to order contestants. Thus points gained in Extra Time are used to rank participants that have the same number of points gained in Normal Time.

If a pair of contestants have the same number of points gained in Normal Time and the same number of points gained in Extra Time, they will be ordered according to the time (in seconds) of the last submission which gave them an improved positive score. For each programming task, we will consider only the best submission (or if there are many submissions which are equally correct, the earliest). For logic puzzles, if you submit new answers in Extra Time, whatever score you would have got is over-written by your new submission, and those points are changed into Extra Time points.

In other words, it's always safe to submit a new answer for programming tasks (you can only improve your situation). It is not always safe to do that for logic puzzles – consider carefully whether or not you want to do that.

The problems will be relativly easy but, I hope, they will be interesting, as will be the contest format.

We will be greatful for all community members who help us in testing.

With best regards, Ivan.

 
 
 
 
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7 years ago, # |
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Its gonna be intresting! I think ;)

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7 years ago, # |
  Vote: I like it +12 Vote: I do not like it

Where did idea come from?

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7 years ago, # |
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Where's the special link?

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7 years ago, # |
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Sounds interesting! But why a logic puzzle...?

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7 years ago, # |
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Is it rated?

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    7 years ago, # ^ |
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    "Today (16:00 UTC) we want you to take part in testing and unrated round with unussual scoring system."

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7 years ago, # |
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Where's the special link?

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7 years ago, # |
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where we can take part in contest?

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7 years ago, # |
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It seems to be starting soon. $10 says that A+B problem will appear. Good Luck.

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    7 years ago, # ^ |
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    You Loos.. Send me the $10.. :D

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7 years ago, # |
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End of registration. Good luck all!

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7 years ago, # |
  Vote: I like it +12 Vote: I do not like it

The "Alpha Round 2 rules:" page has no scrollbar, and is scrollable only by arrows (and not scrollable by mouse wheel). Firefox 25.0.1.

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7 years ago, # |
Rev. 3   Vote: I like it -8 Vote: I do not like it

I'd prefer opening all problem pages once the contest begins (since the network connection to Codeforces is pretty slow), but opening new tabs caused the resulting tab has no scrollbar in this contest.

Reproduction:

  1. Open Problem List Page.
  2. Middle click (click with middle button) the link of problem H.
  3. You got a page which is not scrollable.

More details:

I got (for example) url "https://ctc.codeforces.com/contest/7/my" by opening new tabs directly, but what I really want is "http://codeforces.com/alpha7#/contest/7/my".

In short, opening new tabs will break out from <iframe>.

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7 years ago, # |
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Why I have 0 points for problem B? It was solved in main time and assuming my answer is correct, points in monitor should be 10

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    7 years ago, # ^ |
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    It was the same bug for me, I submitted answers for some logic puzzle, and they disappeared (or haven't been saved, I don't know), as I noticed later.

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      7 years ago, # ^ |
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      But my answer is not disappeared, and my submission is in submissions list. But points at monitor are 0 (and on mouse hover, "Points in case of all given answers are correct" is shown).

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      7 years ago, # ^ |
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      Can you describe your case in details?

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        7 years ago, # ^ |
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        So, it was problem "Permutation Game", I wanted to submit Test 2 first, but submitted it as Test 1. I noticed that and then resubmitted Test 1 with a different answer, and then submitted Test 2 and Test 3 answers. While solving, I didn't reload the problem page. I closed the problem, and after a while I noticed that I only had 3 points for that problem. I opened it, and there was only Test 1 submission (with my Test 2 answer), so the state before I resubmitted Test 1. Then I submitted the answers again.

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    7 years ago, # ^ |
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    Problem B is logic puzzle, it will be checked after the contest.

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    7 years ago, # ^ |
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    Thanks, we will investigate it. Do you see your answer if open problem statement?

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      7 years ago, # ^ |
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      Yes, I see, and also I can see my submission in the list.

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7 years ago, # |
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Don't know if the same for others users, but each time I try to change the page on standings, I get the "all your bugs are belong to me" page.

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7 years ago, # |
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When you access the scoreboard BUT not on the page you are ON. (For ex, your standing is in 3rd page(41-60), and you tried to access the 1st page, a error message come. (The one that says that all bug belongs to me)

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7 years ago, # |
  Vote: I like it -8 Vote: I do not like it

My first submission is at 01:00:06 & my last submission is at 01:28:46 Why my last submission is in extra time?

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    7 years ago, # ^ |
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    You started the contests before your first submission. It is when you press "Start contest" button.

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7 years ago, # |
Rev. 3   Vote: I like it +1 Vote: I do not like it

Lets share our answers to logic problems.

Mine answers are:

A) 366; 800

B) 5

C) BABA; CBABBA

D) CADB; EBDFAC; CEFIBHADG

E) 8; 23

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    7 years ago, # ^ |
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    A:367, 792 B:11 C:BABA, CBABBCC D:CADB, EBDFAC, CEFIBHADG E:8, 23 :D

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    7 years ago, # ^ |
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    Yeah, I got the same. :)

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    7 years ago, # ^ |
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    Same except A) 366; 792 Edit: Oh... Stupid me

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      7 years ago, # ^ |
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      In A2 you should output maximum number of pages. Pages from 792 to 800 do not have any ones in their decimal representation, so I guess 800 is correct.

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    7 years ago, # ^ |
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    Mine are same.

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      7 years ago, # ^ |
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      In program 3, I got partial result, I don't know what did I miss. Can you look at my code and tell me what's wrong. Solution

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        7 years ago, # ^ |
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        We can't access to solutions for moments, but I had myself partial result for one reason:

        I didn't took in account the fact that two country having the same amount of medals had the same ranking.
        For sample:
        1 GER 2 1 1
        1 RUS 2 1 1

        and not

        1 GER 2 1 1
        2 RUS 2 1 1

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    7 years ago, # ^ |
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    Interestingly, ABBABC also works, and is a reverse of your answer.

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      7 years ago, # ^ |
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      Does it?

      ((3+3)*2*2+3)*2+1=55

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        7 years ago, # ^ |
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        Oh damn. It works if we start with 2, not 3.

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7 years ago, # |
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It is not a bug, but the right side of the contest page hid when a window size was small (In the same window size, it doesn't hide at usual contests).

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

"A solution is evaluated on a fixed set of tests right after it is submitted. For each passed test, a contestant will get a fixed amount of points. The sum of points for all passed tests is the total points received by the solution."

Let me see if I got this right...

A contestant submits a solution, and instantly gets feedback reporting how many points the solution earned. And a solution can get 80% of the total points of a problem, for example. Did I understand right?

If I did, I must say that I absolutely LOVE the system.

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7 years ago, # |
  Vote: I like it -27 Vote: I do not like it

I love this competition method. The only one I hate is the time limit. The fact that the most matter is the "Normal Time" kinda make this competition anti-climax and anti-programming (CMIIW, but many people only solve the logic game in the normal time. The coding is only on extra time, contradict on what should happen in a coding tourney)

My suggestion: Score at Extra Time MUST BE considered for final score (So your final score= normal time+extra time) However Normal Time is used for tiebreaker.

Up vote this if you like this suggestion.

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

Nice contest, I want more like this. Positive:

  • logical problems

— love running algorithms on brain+paper instead of computer

— very fast + no coding required

— new & unusual

  • duration of important part 30 minutes

  • easy coding problems

Negative:

  • possibly there are vulnerabilities to cheating with these rules

— participants can share their answers to logical problems privately, without any chances from Jury to notice it

— multiple accounts allow to move solution timings from second to first time limit

Best of luck, will be waiting for next one.

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7 years ago, # |
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Are there any plans for more upcoming contests like this one? I really want to take part in contests with this system.

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7 years ago, # |
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put me minus !!!