"""
Constraints:
    -9 <= arr[i][j] <= 9
    0 <= i,j <= 5
"""

def get_hour_glass_sum(arr: List[int], x: int, y: int) -> int:
    first_line = sum([arr[x][y + i] for i in range(3)])
    second_line = arr[x + 1][y + 1]
    third_line = sum([arr[x + 2][y + i] for i in range(3)])
    
    return first_line + second_line + third_line

def hourglassSum(arr):
    greater_sum = None
    
    for x in range(4):
        for y in range(4):
            current_sum = get_hour_glass_sum(arr, x, y)
            
            if greater_sum is None:
                greater_sum = current_sum
                continue
            
            greater_sum = max(current_sum, greater_sum)
            
    return greater_sum