[LeetCode] Max Sum of Rectangle No Larger Than K 最大矩陣和不超過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:

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

Note:

The rectangle inside the matrix must have an area &gt; 0.

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

Credits:

解法一：

解法二：