def main():
"""Main program."""
answer = 10**10
start_time = time.time()
index_n = 1
while True:
index_n += 1
p_number_1 = fn.get_pentagonal_number(index_n)
for index_b in range(index_n - 1, 0, -1):
p_number_2 = fn.get_pentagonal_number(index_b)
diff_p = abs(p_number_1 - p_number_2)
if fn.is_pentagonal(diff_p):
sum_p = p_number_1 + p_number_2
if fn.is_pentagonal(sum_p):
answer = min(answer, diff_p)
break
if answer < 10**10:
break
end_time = time.time()
print("The answer is %d" % answer)
print("%f seconds elapsed." % (end_time - start_time))
import pyperclip
pyperclip.copy(str(answer))
print("The answer has been placed in the clipboard.")
def test_get_pentagonal_number(self):
"""Test get_pentagonal_number()"""
p_numbers = [0, 1, 5, 12, 22, 35, 51, 70, 92, 117, 145]
for index, expected in enumerate(p_numbers):
self.assertEqual(expected, fn.get_pentagonal_number(index))
