path: root/003.ex

n = 600851475143

(for x <- 2..trunc(:math.sqrt(n / 2)), rem(n, x) == 0, do: x)
|> Enum.reduce_while(n, fn x, acc ->
    if acc == x, do: {:halt, x}, else: {:cont, acc / x}
  end)
|> trunc
|> IO.puts