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First solution in Clear category for Moore Neighbourhood by gledi
def count_neighbours(grid, row, col):
xmax = len(grid) - 1
ymax = len(grid[0]) - 1
m = (-1, 0, 1)
deltas = [(dx, dy) for dx in m for dy in m]
neighbors = 0
for dx, dy in deltas:
if dx == 0 and dy == 0:
continue
x = row + dx
y = col + dy
if x < 0 or x > xmax or y < 0 or y > ymax:
continue
neighbors += grid[x][y]
return neighbors
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"
Jan. 23, 2016
