-- 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.

calc :: Int 
calc = sum [x| x <- [1..999], x `mod` 3 == 0 || x `mod` 5 == 0]

main :: IO ()
main = print calc
