This program allows to you check if an integer is positive or negative

a = raw_input(‘Input a number: ‘) aa = int(a)

while aa > 1:         if aa%2:             aa = aa + 3 + 1

if a < 0:     print ‘You entered a negative number.’ else:     print ‘You entered a positive number. Countdown’

while aa % 2:         print aa,         aa = aa * 3 + 1

print print ‘End’