3.11.1 Collatz序列+3.11.2 输入验证

python：

def collatz():global inputnumtry:a=int(inputnum)if a%2==0:print(a//2)return a//2else:print(3*a+1)return a*3+1except ValueError:print('Error: Input an integer')inputnum = input()
while 1:inputnum = collatz()if ( inputnum == 1 ):break