You are given a m x n matrix grid consisting of non-negative integers.

In one operation, you can increment the value of any grid[i][j] by 1.

Return the minimum number of operations needed to make all columns of grid strictly increasing.

 

Example 1:

Input: grid = [[3,2],[1,3],[3,4],[0,1]]

Output: 15

Explanation:

Example 2:

Input: grid = [[3,2,1],[2,1,0],[1,2,3]]

Output: 12

Explanation:

 

Constraints: