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KEYENCE Programming Contest 2023 Autumn（AtCoder Beginner Contest 325） Announcement
By atcoder_official, history, 7 months ago, In English

We will hold KEYENCE Programming Contest 2023 Autumn（AtCoder Beginner Contest 325）.

We are looking forward to your participation!

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7 months ago, # |
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250 for B will it be hard

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7 months ago, # |
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Just want to solve A... I'm to weak...

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7 months ago, # |
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sfs

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7 months ago, # |
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How to solve D ?

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7 months ago, # |
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How to today's D? E was easier than D.

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7 months ago, # |
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problem C was the number of islands, it was a kind of standard graph problem.

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7 months ago, # |
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I solved D, but couldn't solve E.

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7 months ago, # |
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For problem C, why does it not work if I do not use a visited set? It should be sufficient to mark it as empty "." right? Is there an edge case i am missing here?

https://atcoder.jp/contests/abc325/submissions/46818827

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    7 months ago, # ^ |
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    Maybe you referenced $$$grid[n][m]$$$ where $$$n\ge N$$$ or $$$m\ge M$$$?

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7 months ago, # |
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Can someone tell me what is wrong in my solution for problem D?

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7 months ago, # |
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can someone tell what wrong in my solution for D https://atcoder.jp/contests/abc325/submissions/46827017

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    7 months ago, # ^ |
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    You have to use a priority queue. Imagine when you are at time t, and there are two segments which contain t. At this point, it doesn't matter which of these segments begins first. All it matter is which of these segments finish first.

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7 months ago, # |
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can any one tell me what the topic of problem d?

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    7 months ago, # ^ |
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    scheduling trick: pick the first-ending task use cp-handbook greedy section to learn about it

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      7 months ago, # ^ |
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      thank you bro (=

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      6 months ago, # ^ |
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      Not exactly the same problem... if i recall the one in cph disallows choosing another task whilst performing the first one, so the proof for this problem is different from in CPH. However its true the greedy is the same.

      Seems like the proof is a bit difficult... wonder why they omit it in the editorial :|

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7 months ago, # |
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How to solve $$$F$$$? I thought of dp but couldn't think how we gonna do it!

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    7 months ago, # ^ |
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    $$$dp_{i, j} = \min$$$ number of type-2 sensors to cover first $$$i$$$ ranges if we also use $$$j$$$ type-1 sensors

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      7 months ago, # ^ |
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      Thanks!

      tbh I misread constraints for $$$k$$$, assumed that $$$k \le 10^9$$$ :(

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7 months ago, # |
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UPD: Never mind

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7 months ago, # |
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Forbidden

REVEL_CSRF: tokens mismatch.

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7 months ago, # |
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I think problem F is very inspiring, even though I didn't come up with that definition as the editorial mentions.

However, this reminds me of a problem that I have met before, which involves a similar idea https://codeforces.com/contest/745/problem/E.

When I first met some new ideas, I could keep that in mind, maybe for several days, and this time, it shows again that, I will forget it sooner or later. I think I should practice harder and more.

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7 months ago, # |
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Don't know why but Dijikstar's didn't strike to me during the contest and i was bullish on Dp

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7 months ago, # |
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Can anyone help me why this code is wrong for problem G?

https://ideone.com/TZcGWP

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7 months ago, # |
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Could someone expain me this sentence?

You can switch from company car to train, but not vice versa. You can do so without spending time, but only in a city.

Does that mean once I get on the train,I can't get on the car anymore,then I must get to the n city by train?

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7 months ago, # |
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My solution in problem D is almost the same as abc214_e

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7 months ago, # |
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How to solve D? I solved E, but I can't solved D. Who can help me?

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6 months ago, # |
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Can anyone please explain D to me in detail? Why are we not taking the start time first and all that? I am really struggling with this problem and I also didn't find the editorial of much help. Any explanation would be really highly appreciated.

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5 months ago, # |
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can anyone tell me why the 3rd test case of problem B is 67 and not 66? My manual calculation gives 66. But I can't understand how it is 67.

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