def fizzbuzz(x: int) -> str:
    """FizzBuzz

    >>> fizzbuzz(1)
    '1'
    >>> fizzbuzz(3)
    'Fizz'
    >>> fizzbuzz(5)
    'Buzz'
    >>> fizzbuzz(15)
    'FizzBuzz'
    """
    if x % 3 == 0 and x % 5 == 0:
        return "FizzBuzz"
    elif x % 3 == 0:
        return "Fizz"
    elif x % 5 == 0:
        return "Buzz"
    return str(x)