// fizzBuzz: any number divisible by 3 is Fizz and any number divisible by 5 is Buzz and both is FizzBuzz.
func fizzBuzz(n int) string {
	var buf bytes.Buffer

	for i := 1; i <= n; i++ {
		if i%15 == 0 {
			fmt.Fprintln(&buf, "Fizz Buzz")
		} else if i%3 == 0 {
			fmt.Fprintln(&buf, "Fizz")
		} else if i%5 == 0 {
			fmt.Fprintln(&buf, "Buzz")
		} else {
			fmt.Fprintln(&buf, i)
		}
	}
	return buf.String()
}