Leetcde-931. Minimum Falling Path Sum

Original link: https://leetcode.com/problems/minimum-falling-path-sum/

For elements in the second line and below, we can search the upper two or three elements and add the minimum value.
Boundary condition: elements in the most left and the most right. They can only search for two elements.

Code:

class Solution(object):
    def minFallingPathSum(self, A):
        """
        :type A: List[List[int]]
        :rtype: int
        """
        
        for r in range(1, len(A)):
            
            A[r][0] += min(A[r-1][0], A[r-1][1])
            
            for c in range(1, len(A[r]) - 1):
                
                A[r][c] += min(A[r-1][c-1:c+2])

            A[r][-1] += min(A[r-1][-2], A[r-1][-1])
        
        return min(A[-1])