def sign(n):
    """ A matematikai elojel fuggveny. """
    if n == 0:
        return 0
    if n < 0:
        return -1
    else:
        return +1


def test(num, condition):
    """ A teszt eredmenyet irja ki. """
    if condition:
        print("Test {0} rendben van.".format(num))
    else:
        print("Test {0} ELBUKOTT.".format(num))


def test_suite():
    """ A tesztkeszlet vegrehajtasa. """
    test(1, sign(17) == 1)
    test(2, sign(-17) == -1)
    test(3, sign(0) == 0)
    test(4, sign(3.14) == 1)
    test(5, sign(-2.718281) == -1)


test_suite()