import os


# Find the sum of all number that are divisible by either 3 or 5 below 1000

threes = set()
fives = set()

for x in range(334):
    threes.add(3*x)

for x in range(200):
    fives.add(5*x)


threesfives = threes.union(fives)

print(sum(threesfives))