Minimum Falling Path Sum

Given an n x n array of integers matrix, return the minimum sum of any falling path through matrix.

A falling path starts at any element in the first row and chooses the element in the next row that is either directly below or diagonally left/right. Specifically, the next element from position (row, col) will be (row + 1, col - 1), (row + 1, col), or (row + 1, col + 1).

Input Format:

First parameter: size of 2D array matrix.

Second parameter: 2D array matrix of numbers

Output Format:

Return the number.

Example 1:

Input: 
3 3
2 1 3
6 5 4
7 8 9
Output: 
13
Explanation: There are two falling paths with a minimum sum as shown.

Example 2:

Input: 
2 2
-19 57
-40 -5
Output: 
-59
Explanation: The falling path with a minimum sum is shown.

Constraints:

• n == matrix.length == matrix[i].length
• 1 <= n <= 100
• -100 <= matrix[i][j] <= 100
• Expected Time Complexity: O(n²)
• Expected Space Complexity: O(n)