# -*- coding: utf-8 -*-
"""
S

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.

"""
total = 0

for i in range(1000):
    if i %3 == 0 or i%5 == 0:
        total = total + i
print(total)