使用变量作为标识符向列表中输入项目

在尝试用 Python 编程中，我遇到了这样一个问题：我想让用户指定一个公司中股东的数量，然后询问每位股东在三个品质上的评级（工作的有用性、工作的意义和工作的难度）。我想把用户的这些评级数据存储起来，以便以后显示。为了解决这个问题，我尝试使用三个不同的列表来分别存储这三个品质的评级，并使用一个变量 userrem 作为标识符来向每个列表中添加项目。然而，在执行代码时，我遇到了 IndexError: list assignment index out of range 的错误。

2、解决方案

这个问题有几个不同的解决方法：

• 使用字典代替列表。字典是一种更灵活的数据结构，它允许使用变量作为键来访问其中的值。这样，就可以轻松地向字典中添加新的项目，而无需担心索引越界的问题。

• 使用列表推导式。列表推导式是一种简洁的语法，可以用来创建列表。使用列表推导式，可以将输入的数据直接转换为列表中的项目，而无需使用循环。

• 预先创建列表。如果知道列表中项目的数量，可以预先创建列表，然后向其中添加项目。这样可以避免出现索引越界的问题。

• 使用元组。元组是一种不可变的数据类型，可以用来存储多个值。可以使用元组来存储每个股东的三个评级，然后将元组添加到列表中。

下面是一个使用字典的示例代码：

usefulness = {}
significance = {}
difficulty = {}

user_n = int(input('How many shareholders are there?'))

for i in range(user_n):
    userrem = i
    usefulness[userrem] = int(input('Rate the usefulness of the work performed by shareholder# '+str(userrem+1)+' [Range=0-5]'))
    significance[userrem] = int(input('Rate the significance of the work performed by shareholder# '+str(userrem+1)+' [Range=0-5]'))
    difficulty[userrem] = int(input('Rate the difficulty of the work performed by shareholder# '+str(userrem+1)+' [Range=0-5]'))

print(usefulness)
print(significance)
print(difficulty)

下面是一个使用列表推导式的示例代码：

user_n = int(input('How many shareholders are there?'))

usefulness = [int(input('Rate the usefulness of the work performed by shareholder# '+str(i+1)+' [Range=0-5]')) for i in range(user_n)]
significance = [int(input('Rate the significance of the work performed by shareholder# '+str(i+1)+' [Range=0-5]')) for i in range(user_n)]
difficulty = [int(input('Rate the difficulty of the work performed by shareholder# '+str(i+1)+' [Range=0-5]')) for i in range(user_n)]

print(usefulness)
print(significance)
print(difficulty)

下面是一个预先创建列表的示例代码：

user_n = int(input('How many shareholders are there?'))

usefulness = [None] * user_n
significance = [None] * user_n
difficulty = [None] * user_n

for i in range(user_n):
    userrem = i
    usefulness[userrem] = int(input('Rate the usefulness of the work performed by shareholder# '+str(userrem+1)+' [Range=0-5]'))
    significance[userrem] = int(input('Rate the significance of the work performed by shareholder# '+str(userrem+1)+' [Range=0-5]'))
    difficulty[userrem] = int(input('Rate the difficulty of the work performed by shareholder# '+str(userrem+1)+' [Range=0-5]'))

print(usefulness)
print(significance)
print(difficulty)

下面是一个使用元组的示例代码：

user_n = int(input('How many shareholders are there?'))

scores = []

for i in range(user_n):
    userrem = i
    usefulness = int(input('Rate the usefulness of the work performed by shareholder# '+str(userrem+1)+' [Range=0-5]'))
    significance = int(input('Rate the significance of the work performed by shareholder# '+str(userrem+1)+' [Range=0-5]'))
    difficulty = int(input('Rate the difficulty of the work performed by shareholder# '+str(userrem+1)+' [Range=0-5]'))
    scores.append((usefulness, significance, difficulty))

print(scores)

建议选择最适合您具体需求的解决方案。