renovated2020's blog

K length substring
By renovated2020, 10 years ago, In English

What is the most efficient algorithm or approach for finding most frequent k-length sub-string from a given string?

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10 years ago, # |
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Hash all substrings of length K in O(N) and store this values in map O(NlogN)

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    10 years ago, # ^ |
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    It would be O(NKlogN)

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      10 years ago, # ^ |
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      Hash all substrings of length K

      If you implement rolling hashes it would be O(N*logN).

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        10 years ago, # ^ |
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        hash(s1..k) = (hash(s0..k - 1) - s0 * pk) * p + sk

        by this relation hash values can calculate in O(1)

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