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"""

In this problem, we want to rotate the matrix elements by 90, 180, 270

(counterclockwise)

Discussion in stackoverflow:

https://stackoverflow.com/questions/42519/how-do-you-rotate-a-two-dimensional-array

"""

def make_matrix(row_size: int = 4) -> [[int]]:

"""

>>> make_matrix()

[[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12], [13, 14, 15, 16]]

>>> make_matrix(1)

[[1]]

>>> make_matrix(-2)

[[1, 2], [3, 4]]

>>> make_matrix(3)

[[1, 2, 3], [4, 5, 6], [7, 8, 9]]

>>> make_matrix() == make_matrix(4)

True

"""

row_size = abs(row_size) or 4

return [[1 + x + y * row_size for x in range(row_size)] for y in range(row_size)]

def rotate_90(matrix: [[]]) -> [[]]:

"""

>>> rotate_90(make_matrix())

[[4, 8, 12, 16], [3, 7, 11, 15], [2, 6, 10, 14], [1, 5, 9, 13]]

>>> rotate_90(make_matrix()) == transpose(reverse_column(make_matrix()))

True

"""

return reverse_row(transpose(matrix))

# OR.. transpose(reverse_column(matrix))

def rotate_180(matrix: [[]]) -> [[]]:

"""

>>> rotate_180(make_matrix())

[[16, 15, 14, 13], [12, 11, 10, 9], [8, 7, 6, 5], [4, 3, 2, 1]]

>>> rotate_180(make_matrix()) == reverse_column(reverse_row(make_matrix()))

True

"""

return reverse_row(reverse_column(matrix))

# OR.. reverse_column(reverse_row(matrix))

def rotate_270(matrix: [[]]) -> [[]]:

"""

>>> rotate_270(make_matrix())

[[13, 9, 5, 1], [14, 10, 6, 2], [15, 11, 7, 3], [16, 12, 8, 4]]

>>> rotate_270(make_matrix()) == transpose(reverse_row(make_matrix()))

True

"""

return reverse_column(transpose(matrix))

# OR.. transpose(reverse_row(matrix))

def transpose(matrix: [[]]) -> [[]]:

matrix[:] = [list(x) for x in zip(*matrix)]

return matrix

def reverse_row(matrix: [[]]) -> [[]]:

matrix[:] = matrix[::-1]

return matrix

def reverse_column(matrix: [[]]) -> [[]]:

matrix[:] = [x[::-1] for x in matrix]

return matrix

def print_matrix(matrix: [[]]) -> [[]]:

for i in matrix:

print(*i)

if __name__ == "__main__":

matrix = make_matrix()

print("\norigin:\n")

print_matrix(matrix)

print("\nrotate 90 counterclockwise:\n")

print_matrix(rotate_90(matrix))

matrix = make_matrix()

print("\norigin:\n")

print_matrix(matrix)

print("\nrotate 180:\n")

print_matrix(rotate_180(matrix))

matrix = make_matrix()

print("\norigin:\n")

print_matrix(matrix)

print("\nrotate 270 counterclockwise:\n")

print_matrix(rotate_270(matrix))

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