atcoder_official's blog

By atcoder_official, history, 5 days ago, In English

We will hold AtCoder Regular Contest 189 (Div. 2).

The point values will be 400-500-600-700-800.

We are looking forward to your participation!

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5 days ago, # |
  Vote: I like it -18 Vote: I do not like it

i think AI ended ABC, just do ARC, abc is ended

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

    No,it's ABC and ARC DIV.2

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4 days ago, # |
  Vote: I like it +13 Vote: I do not like it

Several months ago, after reaching yellow, I found that it's too hard for me to get positive deltas quickly by participating in ARCs. I even thought that I couldn't reach orange during the whole CP journey.

But now ARCs (Div.2) have come. I have reignited hope once again.

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4 days ago, # |
  Vote: I like it +3 Vote: I do not like it

Does the div system means there will be fewer ARCs (~20 $$$\to$$$ ~8) for oranges? :(

(And there are too few AGCs.)

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4 days ago, # |
  Vote: I like it -14 Vote: I do not like it

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4 days ago, # |
  Vote: I like it +6 Vote: I do not like it

Hope this new contest will be more interesting for the participants like me.

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4 days ago, # |
  Vote: I like it -18 Vote: I do not like it

Why don't you keep it rated for Green ?

I am green on Atcoder. I have been to purple on Codeforces. I want to take part as rated participant on today's contest.

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4 days ago, # |
  Vote: I like it -13 Vote: I do not like it

it should be rated for everyone who wants to participate . I don't know why lower rated participant are not allowed to participate as rated .

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

So what is the difficulty? Is it close to Codeforces Div.2?

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3 days ago, # |
  Vote: I like it +32 Vote: I do not like it

I think task C and D are easier than task A and B. By the way, I think B is an amazing task.

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

    Same. I couldn't solve the B, but when I looked at editorial, I just realised, how simple it was.

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    3 days ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Yes — I solved A, then thought about B

    then solved D then thought about B

    then I knew how to solve C... but at the same time I knew how to solve B

    It's too hard, but at the same time a fresh-style task.

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3 days ago, # |
  Vote: I like it 0 Vote: I do not like it

Any hints for problem E?

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    3 days ago, # ^ |
      Vote: I like it -18 Vote: I do not like it

    dp

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    3 days ago, # ^ |
    Rev. 4   Vote: I like it +16 Vote: I do not like it
    hint1
    hint2
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    5 hours ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    please

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3 days ago, # |
  Vote: I like it +22 Vote: I do not like it

D is a subtask of this olympiad problem, where the full problem is on a tree instead of a line.

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27 hours ago, # |
  Vote: I like it 0 Vote: I do not like it

Alternate solution for D using only stack in O(n).

https://atcoder.jp/contests/arc189/submissions/60641416