python - 需要帮助用计数器将 else 放入 while

Question

password = str()

while password != "changeme":
    password = input("Password: ")
print("Thou Shall Pass Into Mordor")
else print("Thou Shall Not Pass Into Mordor")

请问我的代码有一些 helo 吗？

我希望它在密码错误 5 次时打印“Though Shall Not Pass Into Mordor”。有人可以帮帮我吗!有人也可以放一个计数器吗？

Answer 1

使用 break 结束循环，并使用 for 和 range():

for attempt in range(5):
    password = input("Password: ")
    if password == "changeme":
        print("Thou Shall Pass Into Mordor")
        break
else:
    print("Thou Shall Not Pass Into Mordor")

for 循环的else 分支仅在您没有使用break 结束循环时执行循环。

演示:

>>> # Five failed attempts
...
>>> for attempt in range(5):
...     password = input("Password: ")
...     if password == "changeme":
...         print("Thou Shall Pass Into Mordor")
...         break
... else:
...     print("Thou Shall Not Pass Into Mordor")
... 
Password: You shall not pass!
Password: One doesn't simply walk into Mordor!
Password: That sword was broken!
Password: It has been remade!
Password: <whispered> Toss me!
Thou Shall Not Pass Into Mordor
>>> # Successful attempt after one failure
...
>>> for attempt in range(5):
...     password = input("Password: ")
...     if password == "changeme":
...         print("Thou Shall Pass Into Mordor")
...         break
... else:
...     print("Thou Shall Not Pass Into Mordor")
... 
Password: They come in pints?! I'm having one!
Password: changeme
Thou Shall Pass Into Mordor