HekpoMaH's blog

Any Idea
By HekpoMaH, 11 years ago, In English

I am wondering about how to find the k-th biggest number in an array with less complexity than O(nlogn). Any ideas?

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11 years ago, # |
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There is an O(n) algorithm for finding the kth order statistic (the kth smallest element) in the array. For finding the kth biggest element you can change comparator or just inverse signs of all numbers in the array. Algorithm that works O(n) in the worst case is described in Wikipedia: http://en.wikipedia.org/wiki/Selection_algorithm ("Linear general selection algorithm").

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    11 years ago, # ^ |
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    you can change comparator or just inverse signs of all numbers in the array

    even simpler , change k to n-k+1

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11 years ago, # |
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O(n) algorithm is also described here

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11 years ago, # |
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Your nickname reminds me something...

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