Citadel–styleSoftware EngineerSoftware EngineerQuestion #18

Given a matrix and the top-left and bottom-right coordinates of a submatrix, calculate the sum of the submatrix in (1) linear time and (2) constant time. You are allowed to preprocess the matrix.

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State the assumptions, try a simple case, then work toward a general solution. Check the result and explain how it changes if an assumption changes.

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