363. Max Sum of Rectangle No Larger Than K

Given a non-empty 2D matrix matrix and an integer k, find the max sum of a rectangle in the matrix such that its sum is no larger than k.

Example:

Given matrix = [

[1, 0, 1],

[0, -2, 3]

]

k = 2

The answer is 2. Because the sum of rectangle [[0, 1], [-2, 3]] is 2 and 2 is the max number no larger than k (k = 2).

Note:

The rectangle inside the matrix must have an area > 0.

What if the number of rows is much larger than the number of columns?

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历史题目和总结见公众号「每日一道算法题」

https://leetcode.com/problems/max-sum-of-rectangle-no-larger-than-k/description/