zscoder's blog

Google Code Jam World Finals 2019
By zscoder, history, 5 years ago, In English

According to the official site, GCJ finals starts today at 19:30 UTC but the live stream starts at 22:00 UTC. Is 19:30 UTC the start of the practice round or the actual round? Does anyone know about it?

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  • Vote: I do not like it

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5 years ago, # |
  Vote: I like it +35 Vote: I do not like it

I think live stream is during the last 90 minutes of the competition. The stream is one big ad anyway so whatever.

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

See here for the contest (currently counting down to 19:30 UTC).

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

I haven't been able to follow the competition much this year. Can I find the names of the finalists somewhere?

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5 years ago, # |
  Vote: I like it +9 Vote: I do not like it

Best luck to ainta molamola.!!

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

Does anyone know how to put files on the Desktop in the provided computer?

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    5 years ago, # ^ |
      Vote: I like it +38 Vote: I do not like it

    search for Tweak Tool -> Desktop -> set "Icons on Desktop" to On

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5 years ago, # |
← Rev. 4   Vote: I like it +38 Vote: I do not like it

tourist won !

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    5 years ago, # ^ |
      Vote: I like it +3 Vote: I do not like it

    implying scoreboard means anything in new format

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

    It's already been for 6 years my friend, old news, no surprise ;)

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5 years ago, # |
  Vote: I like it +11 Vote: I do not like it

Huh, the problem were so hard (as always I guess?). I did poor man's virtual contest without any submissions and in an optimistic scenario I would have juggling1 large + juggling2 small + goto small xd (what amounts to astounding 51 points). And what is more, my code to juggling1 is some time heuristic xd. It may fit in time, it may not, depending on tests, I guess. I think I know how to solve big goto, but lacked a bit time to code it.

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    5 years ago, # ^ |
      Vote: I like it -55 Vote: I do not like it

    Then how gennady and mnbvmnr solved them if its too hard ?

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      5 years ago, # ^ |
        Vote: I like it +21 Vote: I do not like it

      Cause they are good I guess? It's not really impossible for them to solve some problem if I say that it's pretty hard.

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        5 years ago, # ^ |
          Vote: I like it -90 Vote: I do not like it

        your maxx rating is 3100+ , even if you find it difficult what about other participants. 2500+ range. i think if they can solve then one with 3000+ can also as you must have read most of concepts and tricks that are required. :)

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          5 years ago, # ^ |
            Vote: I like it +21 Vote: I do not like it

          Rating is just a number. Don't use it as a scale to judge one's performance. It's not nice to say: "You must be able to solve this problem because you are red."

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    5 years ago, # ^ |
      Vote: I like it +45 Vote: I do not like it

    Glad to hear people finding it hard. Other judges were saying the problems were too easy (some people guessed that winner will have 200 points) and I was scared to admit that I found the problems really hard :(.

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      5 years ago, # ^ |
        Vote: I like it -93 Vote: I do not like it

      Then how gennady and rng58 solved them?

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        5 years ago, # ^ |
          Vote: I like it +23 Vote: I do not like it

        Because they are not green like you.

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          5 years ago, # ^ |
            Vote: I like it +10 Vote: I do not like it

          Perhaps you should write grey. One more contest and he would become newbie most probably

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        5 years ago, # ^ |
          Vote: I like it +57 Vote: I do not like it

        Are you trying to ask questions, or are you just trying to be annoying?

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      5 years ago, # ^ |
        Vote: I like it +11 Vote: I do not like it

      Come on, estimating the difficulty is a very important part of tester's job. If some organizers are scared to be honest, a contest turns out very hard and/or problems aren't sorted correctly by difficulty (what indeed happened here). I never thought negatively about a person who gives me feedback that some problem is very hard.

      And I think a lot of people think about the difficulty/complexity of an intended solution instead of the difficulty of coming up with one. That's a very bad thing.

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        5 years ago, # ^ |
          Vote: I like it +11 Vote: I do not like it

        Well, it's really hard to estimate difficulty of come up with solution, when you already know one. I don't think anyone doing that purposefully.

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

        Well first of all, the problems were easier than last year. I also correctly guessed that winner will have ~150 points (which is reasonable). So there was no issue.

        I also wasn't involved in problem selection. I was in discussion of setting scores and guessing how many points winner will get, both doesn't affect problemset.

        Lastly, I wasn't able to solve last few problems / didn't code them, so I can't have strong / meaningful opinions on the set.

        Edit: GCJ doesn't have testers (though some people did solve the whole set). I only created yeah data for 1 problem.

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          5 years ago, # ^ |
            Vote: I like it +26 Vote: I do not like it

          "GCJ doesn't have testers" sounds like
          1. a lie
          2. a very stupid decision

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            5 years ago, # ^ |
            ← Rev. 3   Vote: I like it 0 Vote: I do not like it

            It doesn't have testers who solve whole problemset. We have

            • testers for each problem.
            • internal rounds where people can solve the problems and give feedback.

            It's different from what being said here, where Errichto implied that there should be someone who test solve the set and say the problemset is too difficult.

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

              "internal rounds" should be good for that kind of testing, right?

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                5 years ago, # ^ |
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                Not really, since it doesn't have 1:1 mapping. Imo it's only used to make sure problems are correct.

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

              I didn't say anything about "the set".

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

                So I misunderstood what you were trying to say.

                No single problem was too difficult for the final.

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

                  The feedback should be: this problem is hard, it should be worth a lot of points.

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

                  I was in discussion for allocating scores, and I believe the scores were optimal.

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

When will they announce the final results?

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5 years ago, # |
  Vote: I like it +11 Vote: I do not like it

How does he win every time!!!

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5 years ago, # |
  Vote: I like it +51 Vote: I do not like it

Why problem editorials on onsite contests are always so fast and very hard to comprehend so that I don't even understand solutions to the problems I solved :f?

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5 years ago, # |
  Vote: I like it -152 Vote: I do not like it

If luck had a face....

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    5 years ago, # ^ |
      Vote: I like it +22 Vote: I do not like it

    What are you talking about?

    Gennady is the face of hard work. He is competing for international competitions since is 11 years old. And he started coding when he was 7/8 years (read in an interview a while ago). All he won was his merit, not luck.

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5 years ago, # |
  Vote: I like it +3 Vote: I do not like it

I'm a fan of tourist!

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5 years ago, # |
← Rev. 2   Vote: I like it +13 Vote: I do not like it

I have just recalled that Petrozavodsk Winter 2016 featured a very similar problem to yesterday's E, but even harder one. On GCJ it sufficed to find the leftmost/rightmost intersections and check something trivial, while in this Petrozavodsk problem you needed to deal with some deleted intersections what introduced some more logic (but it can be dealt more or less brutally since at most 100 lines are affected by these deletions).

Too bad that this problem 3,5 years ago seemed pretty easy to me (even though it was the first and only problem in my life where I used point-line duality) and I even coded it during competition, but unfortunately it didn't pass because of precision issues combined with a very tight TL (1s for O(nm) in geometry, where $$$n \le 10^5, m \le 50$$$?) and yesterday I was completely clueless when trying to come up with the solution. Fact that I had precision issues then would make sense when compared to the fact that organizers mentioned big integers (or at least fractions with int128) were required.

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    5 years ago, # ^ |
      Vote: I like it +18 Vote: I do not like it

    I think ecnerwala don't have any precision/biginteger problems.

    His idea is that after sorting points in good order (by angle of segment, first lower point, than upper point in reversed order as I understand, may be he will correct me), the condition "line with this segment intersect all other semgments" implies all points on segment on this order are on the same side of line, which can be checked in O(log^2) time not very hard (segment tree with convex hulls, and binary search on each of logn hulls). Only 25 will fail this check, let's process them naively.

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    5 years ago, # ^ |
      Vote: I like it -76 Vote: I do not like it

    Swistakk its common. as the age and time passes your mind idoesnt work that fast and clever as it used to be in young days.

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      5 years ago, # ^ |
        Vote: I like it +18 Vote: I do not like it

      I'll better watch out for grey hair. If I will have any hair at all.

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      5 years ago, # ^ |
        Vote: I like it +67 Vote: I do not like it

      just die already

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

        The proper term is "minecraft yourself".

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          5 years ago, # ^ |
          ← Rev. 2   Vote: I like it +10 Vote: I do not like it

          There are a lot of euphemisms for that. For example, we in MIPT sometimes use "to make a step into science"

          However despite we discuss here proper terms about suicide let me clarify that this is not like we all agree that vintage Petr should kpm himself which is not even a question now and we are thinking of how we call it

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5 years ago, # |
  Vote: I like it +8 Vote: I do not like it

Oh my god, are we done?
I am so tired.
I don't know if this is live. Oh, I gues it is not live.
It is not live.

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