HisBinarytree's blog

By HisBinarytree, history, 2 years ago, In English

Hello everyone! I am new to competitive programming. (I just started 3 days ago and today i gave my first contest)
it might be probably because I am brain ded but I am unable to understand what is xi and how we are choosing it in the problem (Musical Rods which is the 7th problem in division 4) — Link of the problem.
I am unsure how and where to ask such doubts in Codechef so I thought to make a blog here

Also as everyone is thanking the person who helped them come into competitive programming i would like to thank youtube for recommending me SecondThread's video about 4 days back! I am learning java because of him will try to improve as much as possible :)


(I cant draw :| )

ashibh thx for answering. I cant post images in comments yet so I have to write like this:
so this is what i understood tell me where i am wrong?
4
2 8 9 11
25 27 100 45
this is one of the sample test case where they took
order : 2->4 -> 3-> 1
so according to me following this order


but this doesnot match the x1 values they gave

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2 years ago, # |
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The problem is actually very similar to a recent AtCoder problem the editorial of which you can see here.

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2 years ago, # |
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Basically, Xi is the starting position of every rod starting from 0 as the origin, we arrange rods in such a way that the sum of xi(distance from the origin)*Bi(beauty) becomes maximum hope you get the intuition. :)