第一题：做了一个状态机，100%，代码一般，大佬轻喷，第三题用的dfs，只过了80%，就不贴了 思路是状态变化，start就是开始状态（后面可以接NOT或者命令），cmd状态是命令状态，可以接AND或者OR，NOT是NOT符号，只可以接命令。另外is_bigger就是判断命令是不是大写，大写的话也不符合要求。最后一条命令也要处理下，必须是一个命令，不能是NOT AND 或者OR就行。 import sys def is_bigger(cmd): if cmd >= &#39;A&#39; and cmd <="Z": return True else: return False def judge(lists): cmd_lists = ["AND","OR"] cmd_lists_NOT = ["AND","OR","NOT"] state = "start" for cmd in lists: if state == "start": if cmd == "NOT": state = "NOT" continue if cmd not in cmd_lists and not is_bigger(cmd): state = "CMD" continue print("0") return if state == "NOT": if cmd not in cmd_lists_NOT and not is_bigger(cmd): state = "CMD" continue print("0") return if state == "CMD": if cmd in cmd_lists: state = "start" continue print("0") return if state == "CMD": print("1") else: print("0")