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Fortran-style solution in Clear category for Moore Neighbourhood by dronnix
def count_neighbours(grid, row, col):
getter = lambda grid, row, col: grid[row][col] if 0 <= row < len(grid) and 0 <= col < len(grid[0]) else 0
result = 0
for r in range(row-1, row+2):
for c in range(col-1, col+2):
result += getter(grid, r, c)
return result - getter(grid, row, col)
if __name__ == '__main__':
#These "asserts" using only for self-checking and not necessary for auto-testing
assert count_neighbours(((1, 0, 0, 1, 0),
(0, 1, 0, 0, 0),
(0, 0, 1, 0, 1),
(1, 0, 0, 0, 0),
(0, 0, 1, 0, 0),), 1, 2) == 3, "1st example"
assert count_neighbours(((1, 0, 0, 1, 0),
(0, 1, 0, 0, 0),
(0, 0, 1, 0, 1),
(1, 0, 0, 0, 0),
(0, 0, 1, 0, 0),), 0, 0) == 1, "2nd example"
assert count_neighbours(((1, 1, 1),
(1, 1, 1),
(1, 1, 1),), 0, 2) == 3, "Dense corner"
assert count_neighbours(((0, 0, 0),
(0, 1, 0),
(0, 0, 0),), 1, 1) == 0, "Single"
Oct. 7, 2014
