做了好久感觉好傻都不知道哪错了

a=int(input()) b=a list=[] while (a>1): if a%2==1: a=int(a*3+1) list.insert(0,a) if a%2==0: a=int(a/2) list.insert(0,a) print(" ".join('%s' %id for id in list),b)