Max Sum Without Adjacent Elements

Given a 2 x N grid of integer, A, choose numbers such that the sum of the numbers
is maximum and no two chosen numbers are adjacent horizontally, vertically or diagonally, and return it.

Note: You can choose more than 2 numbers.

Input Format:

The first and the only argument of input contains a 2d matrix, A.

Output Format:

Return an integer, representing the maximum possible sum.

Constraints:

1 <= N <= 20000
1 <= A[i] <= 2000

Example:

Input 1:
    A = [   [1]
            [2]    ]

Output 1:
    2

Explanation 1:
    We will choose 2.

Input 2:
    A = [   [1, 2, 3, 4]
            [2, 3, 4, 5]    ]
    
Output 2:
    We will choose 3 and 5.

NOTE: You only need to implement the given function. Do not read input, instead use the arguments to the function. Do not print the output, instead return values as specified. Still have a question? Checkout Sample Codes for more details.