3402 - Minimum Operations to Make Columns Strictly Increasing.

Easy

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:

• To make the <code>0^th</code> column strictly increasing, we can apply 3 operations on grid[1][0], 2 operations on grid[2][0], and 6 operations on grid[3][0].

• To make the <code>1^st</code> column strictly increasing, we can apply 4 operations on grid[3][1].

Example 2:

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

Output: 12

Explanation:

• To make the <code>0^th</code> column strictly increasing, we can apply 2 operations on grid[1][0], and 4 operations on grid[2][0].

• To make the <code>1^st</code> column strictly increasing, we can apply 2 operations on grid[1][1], and 2 operations on grid[2][1].

• To make the <code>2^nd</code> column strictly increasing, we can apply 2 operations on grid[1][2].

Constraints:

• m == grid.length

• n == grid[i].length

• 1 <= m, n <= 50

• 0 <= grid[i][j] < 2500