def main():
"""Main program."""
# This is my first, brute force solution.
# The spiral of the required dimensions is
# represented by a matrix and the diagonal
# sum calculated by visiting each cell in
# the two diagonals.
answer = 0
start = time.time()
spiral = spirals.build_spiral(1001, 1001)
answer = spirals.diagonal_sum(spiral)
end = time.time()
print("The answer is %d" % answer)
print("%f seconds elapsed." % (end - start))
# After verifying the above solution, I
# ran matrices 3x3, 5x5, 7x7, and 9x9.
# I noticed the patter in the corners
# and so I came up with a second solution.
# I used the data from OEIS sequence A114254
# to verify that this method of calculating
# the diagonal sums is correct.
start = time.time()
answer = spirals.calculate_diagonal_sum(1001)
end = time.time()
print("The answer is %d" % answer)
print("%f seconds elapsed." % (end - start))
import pyperclip
pyperclip.copy(str(answer))
print("The answer has been placed in the clipboard.")
def test_diagonal_sum(self):
"""Test diagonal_sum()"""
spiral = spirals.build_spiral(3, 3)
self.assertEquals(25, spirals.diagonal_sum(spiral))
spiral = spirals.build_spiral(5, 5)
self.assertEquals(101, spirals.diagonal_sum(spiral))