#3070

Count Submatrices with Top-Left Element and Sum Less Than k

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Description

You are given a 0-indexed integer matrix grid and an integer k.

Return the number of submatrices that contain the top-left element of the grid, and have a sum less than or equal to k.

Example 1:

Input: grid = [[7,6,3],[6,6,1]], k = 18

Output: 4

Explanation: There are only 4 submatrices, shown in the image above, that contain the top-left element of grid, and have a sum less than or equal to 18.

Example 2:

Input: grid = [[7,2,9],[1,5,0],[2,6,6]], k = 20

Output: 6

Explanation: There are only 6 submatrices, shown in the image above, that contain the top-left element of grid, and have a sum less than or equal to 20.

Solution