You are given an m x n matrix grid and a positive integer k. An island is a group of positive integers (representing land) that are 4-directionally connected (horizontally or vertically).
The total value of an island is the sum of the values of all cells in the island.
Return the number of islands with a total value divisible by k.
Example 1:
Input: grid = [[0,2,1,0,0],[0,5,0,0,5],[0,0,1,0,0],[0,1,4,7,0],[0,2,0,0,8]], k = 5
Output: 2
Explanation:
The grid contains four islands. The islands highlighted in blue have a total value that is divisible by 5, while the islands highlighted in red do not.
Example 2:
Input: grid = [[3,0,3,0], [0,3,0,3], [3,0,3,0]], k = 3
Output: 6
Explanation:
The grid contains six islands, each with a total value that is divisible by 3.
Constraints:
m == grid.lengthn == grid[i].length1 <= m, n <= 10001 <= m * n <= 1050 <= grid[i][j] <= 1061 <= k <= 106