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CandidateNextYear's blog

By CandidateNextYear, history, 2 months ago, In English,

Hello everyone,
I participated in the last round, solved Div2[A-B] within 25 minutes, then moved to 1330C - Dreamoon Likes Coloring which I got stuck solving it until the end of the contest. I waited for the tutorial.. then I finally got this:



Is writing tutorials really about giving the final answer (formula or something), or it's about explaining how we can get to that answer? I'm not judging anyone here. I'm just asking Authors for the upcoming rounds, please don't just give us the final answer, we can find it out from other participants' codes. it's really nice and helpful for lots of people (at least we with low rating) to know the observations and tricks before reaching out to the final answer. Or idk, is it something intuitive and I'm such a noob?

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

completely agree with you.Don't know why they write tutorial in such a thrash way.And now they may say , TheY WaNt YoU To THiNK . But that can be done by looking others solution also.

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2 months ago, # |
  Vote: I like it +30 Vote: I do not like it

Agreed, and I also feel no ill will towards the writers. Problem setting is probably a very different skill from writing tutorials that are clear to people who are right on the boundary of understanding the problems. I usually find more enlightenment in the comments after the contest.

During today's contest, I was able to figure out the 2 "trivial" conditions that obstruct a coloring. And after reading the above formula for $$$pos_i$$$, it wasn't hard to prove:

  1. The $$$m$$$-th coloring covers the $$$n$$$-th square,
  2. Every color is represented: $$$pos_i<pos_{i+1}$$$, and
  3. There are no gaps: $$$pos_{i+1} \leq pos_i + len[i]$$$

But this feels quite backward as I still don't know how to come up with the construction in the first place.

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2 months ago, # |
  Vote: I like it +101 Vote: I do not like it

I Totally agree with you! If I write tutorial in Chinese, I will write almost detail in the tutorial. But limit to my English writing ability, It's so hard to describe what I think... For example, Just each problem of Div. 2 A, B takes me over two hours to complete it. But I will try to add something in the weekend.

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    2 months ago, # ^ |
      Vote: I like it +9 Vote: I do not like it

    No problem ! We appreciate your effort !

    You did a really great job in setting up the contest with short problem statement. It was only $$$A$$$ that could have been easier to understand.

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2 months ago, # |
  Vote: I like it +134 Vote: I do not like it

Now I have added more discussion about this problem, Including some overall strategy to solve construction problems. Feel free to read it : )

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2 months ago, # |
  Vote: I like it 0 Vote: I do not like it

I completely agree, not only is it less useful this way but it is also less readable, sometimes it just feels like they are just trying to fut as much math as possible.