def Main(fibnumber):
    """
    :param fibnumber:
    :return:
    """
    fibresult = fibR(fibnumber)

    return fibresult


def fibR(n):
    """
    :param n:
    :return:
    """
    if n == 1 or n == 2:
        return 1

    return fibR(n - 1) + fibR(n - 2)