Question

我正在完成一个简单的编程练习（我还是新的），我通过为4个不同的角色属性分配30个点来创建角色配置文件。程序功能包括：显示当前配置文件，创建新配置文件或更改现有配置文件。第一个和第二个功能工作正常，但是最后一个问题：该程序旨在解压缩嵌套列表项（属性+分配分数），要求新分数，取旧和新之间的差异并更改数字因此，池中的可用点数。最后，在位置0的列表中添加一个新条目（属性+新分配的分数），然后删除位置1的条目，该条目应该是该属性的旧条目。遍历列表，完成。但是，一旦执行代码，您将看到它不起作用。请参阅下面的完整代码：

options = ["Strength", "Health", "Wisdom", "Dexterity"]
profile = []
points = 30

choice = None
while choice != "0":

    print(
        """
    CHARACTER CREATOR PROGRAM

    0 - Exit
    1 - See current profile
    2 - Build new profile
    3 - Amend existing profile

    """
        )

    choice = input("Please choose an option: ")
    print()

    if choice == "0":
        print("Good bye.")
    elif choice == "1":
        for item in profile:
            print(item)
        input("\nPress the enter key to continue.")
    elif choice == "2":
        print("You can now equip your character with attributes for your adventures.")
        print("You have",points,"points to spent.")
        print("Now configure your character: \n")
        #Run the point allocation loop
        for item in options:
            point_aloc = int(input("Please enter points for " + str(item) + ":"))
            if point_aloc <= points:
                entry = item, point_aloc
                profile.append(entry)
                points = points - point_aloc
                print("\nYour current choice looks like this: ")
                print(profile)
                input("\nPress the enter key to continue.")
            else:
                print("Sorry, you can only allocate", points," more points!")
                print("\nYour current choice looks like this: ")
                print(profile)
                input("\nPress the enter key to continue.")
        print("\nWell done, you have configured your character as follows: ")
        for item in profile:
            print(item)
        input("Press the enter key to continue.")
    elif choice == "3":
        print("This is your current character profile:\n")
        for item in profile:
            print(item)
        print("\nYou can change the point allocation for each attribute.")
        for item in profile:
            point_new = int(input("Please enter new points for " + str(item) + ":"))
            attribute, points_aloc = item
            diff = points_aloc - point_new
            if diff >0:
                points += diff
                print("Your point allocation has changed by", -diff,"points.")
                print(diff,"points have just been added to the pool.")
                print("The pool now contains", points,"points.")
                entry = item, point_new
                profile.insert(0, entry)
                del profile[1]
                input("Press the enter key to continue.\n")
            elif diff <0 and points - diff >=0:
                points += diff
                print("Your point allocation has changed by", -diff,"points.")
                print(-diff,"points have just been taken from the pool.")
                print("The pool now contains", points,"points.")
                entry = item, point_new
                profile.insert(0, entry)
                del profile[1]
                input("Press the enter key to continue.\n")
            elif diff <0 and points - diff <=0:
                print("Sorry, but you don't have enough points in the pool!")
                input("Press the enter key to continue.\n")
    else:
        print("Sorry, but this is not a valid choice!")
        input("Press the enter key to continue.\n")

input("\n\nPress the enter key to exit.")

注意：您需要先创建配置文件才能运行更改。

先谢谢你的帮助!!

Answer 1

正如您对问题的评论所示，您没有以最佳方式提出问题。但是，我看到它有什么问题。我可以向您展示如何修复当前代码，但事实是最佳修复它的方法是完全重写它。当你这样做时，你应该采取以下策略：

将代码分解为多个部分。在这种情况下，我建议您创建几个不同的功能。一个可以被称为main_loop，并且将包含用于循环菜单的逻辑。它不包含任何更新或显示配置文件的代码。相反，它会调用其他函数display_profile，build_profile和amend_profile。这些函数将接受options，profile和points等变量，并返回options和points等值。这将极大地简化您的代码，并使测试和调试更容易。以下是main_loop可能的示例：

def main_loop():
    options = ["Strength", "Health", "Wisdom", "Dexterity"]
    profile = []
    points = 30

    choice = None
    while choice != "0":
        print(menu_string)   #define menu_string elsewhere
        choice = input("Please choose an option: ")
        print()

        if choice == "0":
            print("Good bye.")
        elif choice == "1":
            display_profile(profile)
        elif choice == "2":
            profile, points = build_profile(options, profile, points)
        elif choice == "3":
            profile, points = amend_profile(profile, points)
        else:
            print("Sorry, but this is not a valid choice!")
            input("Press the enter key to continue.\n")

    input("\n\nPress the enter key to exit.")

看看这有多好？现在您要做的就是定义其他功能。有点像...

    def build_profile(options, profile, points):
        # insert logic here
        return profile, points

这种方法的另一个优点是，现在您可以单独测试这些功能，而无需运行整个程序。

使用正确的惯用语进行列表修改。在迭代时修改列表需要特别小心，在某些情况下（例如，当您通过删除或添加已经迭代过的项来更改列表的长度时）它根本不起作用。有一些方法可以对profile做一些尝试，但对于初学程序员，我会建议更简单的方法：只需创建一个新列表！然后返回该列表。因此，在amend_profile函数中，执行以下操作：
```
    def amend_profile(profile, points):
        # other code ...
        new_profile = []
        for item in profile:
            attribute, points_aloc = item
            # other code ...
            new_proflie.append(entry)
        # other code ...

        return new_profile, points
```
另请注意，这是您的主要错误之一;您创建的entry包含(item, point_new)而不是(attribute, point_new)，因此您的新元组中包含item元组，而不是预期的attribute字符串。

Python嵌套列表 - 更改和替换单个项目

1 个答案: