#! python3 """Calculate collatz function""" def collatz(x_value): '''collatz calculation''' if x_value % 2 == 0: x_value = x_value // 2 else: x_value = 3 * x_value + 1 print(x_value) return x_value def get_input(): '''get custom input''' try: return int(input()) except (ValueError, NameError): print('Your should input an integer.') return get_input() N = get_input() if N == 0: print('It would enter an infinite loop.') else: while N != 1: N = collatz(N) print(N)