santa_calus's blog

COCI 2015/2016 3rd round — NEKAMELEONI
By santa_calus, history, 8 years ago, In English

I am trying to solve this problem: NEKAMELEONI I have read the tutorial but I can not understand what it says. Can anyone tell me more about this interesting problem? Thank in advance!

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8 years ago, # |
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You are given an array with N integers ar ( for all i (1<=i<=N) 1<=ar[i]<=K ) and you have M task in each task you are given a x number . if x is 1 you are given 2 more numbers a and b it means you must change ar[a] into b if x is 2 you must find a subarray that contains all [1,K] numbers and it must be the shortest contiguous subarray and you must print its length if there is no subarray that contains all [1,K] numbers you must print "-1" (that is what i understand on the problem , it can be wrong) (sorry for bad english)

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    8 years ago, # ^ |
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    How can we solve this problem? I have read tutorial but I can not understand the way we solve this. Could you tell me how to solve this one? You can find the tutorial here : Tutorial

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      8 years ago, # ^ |
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      segment tree :D but this problem is not easy :D I think the merge function is hard . (I know the solution but It's really hard for me to explain it) how ever I think if you learn segment tree and then you take a look at Petr code , you will understand the solution

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8 years ago, # |
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You have solution on this site https://www.hsin.hr/coci/

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    8 years ago, # ^ |
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    I read that solution but I can not understand. Could you give me any hints to solve this problem?

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