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Maximum Submatrix with distinct elements
By Confused101, history, 8 years ago, In English 
Given a 2D matrix of size nxm (n, m <= 400), Calculate maximum submatrix such that all of its elements are distinct? [maximum submatrix is submatrix whose area is maximum]
P.S.
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8 years ago, # |
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407D - Largest Submatrix 3

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    8 years ago, # ^ |
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    Thankyou! this was the problem I was trying to find. can someone explain how to solve it
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8 years ago, # |
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Suppose you fix two rows of the matrix. Can you come up with a way of calculating the answer for this "slice" in O(m)?

Hint: Incrementing the "right" column will impose some constraints (lower bounds) on the "left" column.

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