maroonrk's blog

AtCoder Regular Contest 162 Announcement
By maroonrk, history, 3 years ago, In English

We will hold AtCoder Regular Contest 162.

The point values will be 300-500-500-700-700-900.

We are looking forward to your participation!

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  • Vote: I do not like it

Comments Comments (18)
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3 years ago, hide # |
 
Vote: I like it +20 Vote: I do not like it

Why some arc have discussions on codeforces but some don't?

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3 years ago, hide # |
 
Vote: I like it -10 Vote: I do not like it

I want to know that too

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

Long time no see, ARC.

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3 years ago, hide # |
 
Vote: I like it -10 Vote: I do not like it

It's ready to start,isn't it?

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

site is working?

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

Nice problems with small $$$N$$$ s.

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3 years ago, hide # |
 
Vote: I like it +16 Vote: I do not like it

Interesting and tricky problems!

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3 years ago, hide # |
 
Vote: I like it +17 Vote: I do not like it

Actually, C can be solved in $$$O(n)$$$.

Screencast with commentary

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3 years ago, hide # |
 
Vote: I like it +10 Vote: I do not like it

I solved A by counting inversions in $$$O(n$$$ $$$log$$$ $$$n)$$$. The idea is creating a new array $$$cnt$$$ where $$$cnt_i$$$ is the number of $$$j$$$ so that $$$i \lt j$$$ and $$$a_i \gt a_j$$$. Then the answer is the number of minimum elements in array $$$cnt$$$. However I can't quite explain why it worked.

For problem B I just try to move the number $$$n$$$ to position $$$n$$$, $$$n-1$$$ to position $$$n-1$$$. When you are down to $$$1$$$ and $$$2$$$, if $$$2$$$ is in front of $$$1$$$, the answer is $$$No$$$. The answer is $$$Yes$$$ otherwise.

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

Actrually,I didn't understand problem A's statement even when I passed the problem.

I just guessed what it may wish me to do.

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

What is an ark everyone is talking about? I'm not sure what it is.

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