Question

我正在用Python创建一个登录安全程序，这个部分总是陷入无限循环中。如果你被锁定，它会一直说“你被锁定了10秒钟”并且无限循环。我该如何解决这个问题？

tries=0
while finalusername!=username or  finalpassword!=password:
tries=tries+1
print "That incorrect. Try again."
print "You have", 5-tries, "tries left."
finalusername= raw_input ("Username:")
finalpassword= raw_input ("Password:") 
while tries>=4:
    print "You have been locked out for 10 seconds. Please call the administrator if this keeps happening."
    sleep (10.0)
    system ('CLS')
    finalusername!=username
    finalpassword!=password

Answer 1

轻松，改变

  while tries>=4:

到

  if tries >= 4:

如果你按照你的代码，当你进入第二个while循环时，变量尝试的值永远不会改变，所以你将永远留在那里。如果将while更改为if，则将执行if语句的主体，然后继续循环。

Answer 2

当while大于4时，您的第二个tries循环会激活，但循环本身永远不会在tries上运行或包含任何其他退出条件。这就是为什么它变得无限。所以tries仍然高于4，循环永远不会停止。

从您的代码中，在我看来，在他们用尽了他们的尝试之后，他们被锁定了10秒然后他们又重新开始了？如果是这样，您希望像这样调整您的代码：

tries=0
while finalusername!=username or  finalpassword!=password:
    tries=tries+1
    print "That incorrect. Try again."
    print "You have", 5-tries, "tries left."
    finalusername= raw_input ("Username:")
    finalpassword= raw_input ("Password:") 
    if tries>=4:
        print "You have been locked out for 10 seconds. Please call the administrator if this keeps happening."
        sleep (10.0)
        system ('CLS')
        tries = 0 #Reset tries counter
        finalusername!=username #I don't think this part is required
        finalpassword!=password #I don't think this part is required

Answer 3

我认为你应该在睡眠后将尝试设置为0，如果没有必要则设置循环。睡眠后，用户应再次尝试5次。

import os
import time

tries=0
finalusername, finalpassword= 'a', 'a'
username, password = None, None


while True:
    finalusername= raw_input ("Username:")
    finalpassword= raw_input ("Password:") 
    if finalpassword == username and finalpassword == password:
        break
    tries=tries+1
    print "That incorrect. Try again."
    print "You have", 5-tries, "tries left."
    if tries>=5:
        print "You have been locked out for 10 seconds. Please call the administrator if this keeps happening."
        time.sleep (10.0)
        os.system('cls')
        tries = 0

如何在Python中修复无限循环？

3 个答案: