nukosya's blog

how to find number of distinct values in submatrix?
By nukosya, 3 months ago, translation, In English

Recently i solved a interesting problem. You have to find number of quadrat submatrix length of K, and number of distinct values of submatrix must be <= q. You have to solve this problem for each k from 1 to n. q <= 10, n <= 1500. After some thought, i understood that i can not solve this problem for q <= 1500. May you give some hints or solution for constant k. Shortly, i want to be able to find number of distinct values in submatrix. Thanks!

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3 months ago, # |
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Is there a bound on the range of numbers the matrix can have?

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    3 months ago, # ^ |
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    yes , in problem it says that there is n^2 distinct numbers in mateix

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3 months ago, # |
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I don't get well your problem, is the problem is "for a given $$$k$$$, find the number of distinct submatrix of length $$$k*k$$$ we can have" or is it "find the maximum/minimum number of distinct elements in a submatrix of length $$$k×k$$$"?

Hints for the first problem
Hints for the second problem
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