Kevin114514's blog

By Kevin114514, history, 6 weeks ago, In English

After the change in difficulty, today's ARC problems seem to be a bit too standard/easy to be like the AtCoder problems we used to know. While it may be harder to set the problems like before that require more thinking and are more challenging now (due to the fact that participants have practiced more or some other reasons), will it be possible for ARC to be open for everyone to propose in the future (meanwhile, keeping the high standard of problems)?

Update: feel free to leave your opinion on what ABC/ARC/AGC problems should be like in the comments >_<

  • Vote: I like it
  • +180
  • Vote: I do not like it

»
6 weeks ago, # |
Rev. 3   Vote: I like it +64 Vote: I do not like it

ABC: Classic problems & Easy problems.

ARC: Easier than AGC, but less classic & trick problems, more Ad-Hoc problems, like before.

AGC: Hard and Ad-Hoc.

»
6 weeks ago, # |
  Vote: I like it +51 Vote: I do not like it

The last three problems in this contest feel like the kind of problem that you'll expect in ABC G or previous Ex. requires high-difficulty algorithm/ math skills,but quite straight forward

»
6 weeks ago, # |
  Vote: I like it -27 Vote: I do not like it

ABC is too easy, it's basically braindead coding for the first 4-5 tasks. Would like to see more math\dynamic programming\something that requires thinking and no standard tasks which are copy-pastes of standard algos. ARC usually is great, as long as there are no interactive tasks.

  • »
    »
    6 weeks ago, # ^ |
      Vote: I like it +77 Vote: I do not like it

    Would like to see more math\dynamic programming\something that requires thinking and no standard tasks which are copy-pastes of standard algos.

    ABC is designed for standard use of algos (if I'm correct), so this should be fine. if you need to practice thinking skills, I think it's better to refer to ARCs.

  • »
    »
    6 weeks ago, # ^ |
      Vote: I like it +1 Vote: I do not like it

    And the last two tasks are very classic. Everyone knows ABC375G < CF1163F.

»
6 weeks ago, # |
  Vote: I like it +28 Vote: I do not like it

I think the main problem is about the difficulty. I would rather have fewer ARCs than too easy ones like today. I still think the problem quality of ARCs and AGCs are very high, and it's the same for today. But I would like to have a harder E and probably another F to make this contest more enjoyable.

Previous ARCs are suitable for participants from blue all the way to orange and even red, but if following ARCs are still of this difficulty, I'm afraid that orange and above coders might solve everything easily, and there's nothing challenging for them.

Considering the fact that AGCs are very rare, I hope ARCs could stay at their previous difficulty and it would be acceptable to have fewer of them.

»
6 weeks ago, # |
  Vote: I like it -11 Vote: I do not like it

I am only able to solve till C most of the time although I solve them fast and sometime I also solve D in ABCs but need to improve and solve D regularly in ABCs now

»
6 weeks ago, # |
  Vote: I like it +42 Vote: I do not like it

Regarding the last point, maroonrk gave a talk at the Astana WF about AtCoder and he talked a little bit about the philosophy behind ABC, ARC, and AGC.

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

Where should i practice classic problems guys

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

    atcoder abc contests D and above problems are often using ideas from classic problems

»
6 weeks ago, # |
  Vote: I like it +87 Vote: I do not like it

The philosophy is this: make ARCs easier, and have more AGCs. For problem proposals, I would suggest you propose AGC problems. If you think your problem is suitable for ARCF (for previous ARCs in terms of difficulty and quality), you may just submit it as an AGC problem, since previous ARCFs are often good enough for AGCs.

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

    Have you considered making the rating upper bound for ARC lower? It's a bit weird to have a problem which most orange coders can solve as the hardest problem in a contest rated for ~2800 >_<

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

      Since I no longer supervise ARC contests I'm not sure about the exact process of selecting the problems. However, if I understand correctly, new ARCs should offer challenging problems for oranges (but not red), and the last round was unexpectedly easier than the new standards. Let's ping snuke for more details.

      • »
        »
        »
        »
        6 weeks ago, # ^ |
        Rev. 2   Vote: I like it +41 Vote: I do not like it

        Currently, the ARC admin has changed, rng_58 and I are discussing and coordinating ARC together. Since the admin change is recent, we are still in a experimental phase.

        The new ARC is planned to have a difficulty that is more suitable for the rated participants. In that sense, we also think that the difficulty of ARC185-E might have been a bit too easy.

        (However, the next round will be an irregular one, as it is a qual of the Japan Open, so it is expected to be very challenging.)

    • »
      »
      »
      6 weeks ago, # ^ |
        Vote: I like it -25 Vote: I do not like it

      We shouldnt base things on one round

      Just the previous round had 4 / 5 red+ problems

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

    I think an ARC round needs a red problem. ARC's rated range is 1200~2799, so many orange coders want to be red by participating in ARC rounds. I think a red coder must have the ability to solve a red problem, so it is necessary to have a 2800+ difficulty problem in ARC.

»
6 weeks ago, # |
  Vote: I like it +20 Vote: I do not like it

Participating in ARC184 is just like:

Oh I passed task A. Oh I can't do anything now, all the other tasks are toooooo hard.

Participating in ARC185 is just like:

Oh I passed tasks A, B and C. Omg why have so many of my classmates passed E.

I think if they can mix ARC184 and ARC185 together (that is, exchange some tasks for two contests), then there will be two better contests.