October 2020
"""
Multiples of 3 and 5
If we list all the natural numbers below 10 that are multiples
of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is
23.
Find the sum of all the multiples of 3 or 5 below 1000.
https://projecteuler.net/problem=1
"""
# test
# result = list()
# for n in list(range(10))[1:]:
# if n % 3 == 0 or n % 5 == 0:
# result.append(n)
# assert(sum(result) == 23)
# solution
result = list()
for n in list(range(1000))[1:]:
if n % 3 == 0 or n % 5 == 0:
result.append(n)
print(sum(result))
# 233168