#!python import sys def is_stepping(number: str): number = str(number) seq = str(number)[0] for i in number[1:]: if abs(int(i)-int(seq)) != 1: return 0 seq = i return 1 assert len(sys.argv) == 3 for i in range(int(sys.argv[1]), int(sys.argv[2])+1): if is_stepping(i): print(i) # TESTS assert is_stepping(100) == 0 assert is_stepping(123) == 1 assert is_stepping(321) == 1 assert is_stepping(989) == 1