python - 如何在Python中使代码循环3次并在其周围有一个while循环

Question

使用 python 非常有限并且完全卡住了，我设法在下面的代码上运行一个 while 循环，以便用户可以不断输入代码，直到输入正确的代码。

我现在想做的是添加一个 for 循环，这样它只要求用户输入代码(4 个错误的数字)3 次，然后将其锁定。同时，它需要一个 while 循环来确保如果用户输入的数字多于或少于 4 位，它会持续运行并且不会将其锁定。

我只是无法让 for 循环和 while 循环同时工作，并且不知道我做错了什么。

user = ("1234")

valid = False

while not valid:

   #for i in range (3):  

        user = input("Hello, welcome! Please enter a four digit passcode to open the safe: ")
        user = user.upper()          

        if user == ("1234") :
            print("You have cracked the code, well done")
            valid = True
            break

        if user != ("1234") :
            print ("that is incorrect, please try again")
            valid = False



        elif len(user) > 4:
            print ("That is incorrect, please try again")
            valid = False

        elif len(user) < 4:
            print ("That is incorrect, please try again")
            valid = False
        else:
            print ("You have been locked out!! Alarm!!!!!!")

Answer 1

user = ("1234")

counter = 0

while counter < 3:

    user = input("Hello, welcome! Please enter a four digit passcode to open the safe: ")
    user = user.upper()         

    if len(user) != 4:
        print("I said 4 digits!")
        continue

    if user == ("1234") :
        print("You have cracked the code, well done")
        break

    print ("that is incorrect, please try again")
        counter += 1

if counter == 3:
    print ("You have been locked out!! Alarm!!!!!!")
else:
    print ("Everything is fine.")