def gcd(a, b):

    while b != 0:

        a, b = b, a % b

    return a

if __name__ == '__main__':

    tc1 = gcd(48, 64)

    if tc1 != 16:

        print "Test failed for the case a=48 and b=64. Expected 16. Obtained %d instead." % tc1

        exit(1)

    tc2 = gcd(44, 19)

    if tc2 != 1:

        print "Test failed for the case a=44 and b=19. Expected 1. Obtained %d instead." % tc2

        exit(1)

    print "All tests passed!"