如果满足特定条件，是否可以将值添加到列表中？

Question

是否可以制作一个代码，在输入您的分数和姓名后显示您所在的位置？

#name_score before input and execution 
name_score = [['Never', '69'], ['Gonna', '66'], ['Give', '65'], ['You', '64'], ['Up', '62'], ['Never', '60'], ['Gonna', '59'], ['Let', '55'], ['You', '54'], ['Down', '53']]

name = input('Enter your name: ')
score = int(input('Enter your score: '))

scores = []
for x in name_score:
    scores.append(x[1])

if score in range (int(scores[9]), int(scores[0])):
    name_score.append([name, score])

print(name_score)

我当前代码的问题是我无法找到数字可以进入的确切位置，因此在执行.append()我只能将它带到代码的后面。 如果我使用索引，如果我的分数不在列表中，他们会给我一个值错误， eg if my score is 67, they cant return me a position 。

预期结果：

#program when it is executed *Example 1* 

Enter your name = Mark
Enter your score = 54
Congratulations! You are position 10 on the score board.
 

#name_score after user input
name_score =  [['Never', '69'], ['Gonna', '66'], ['Give', '65'], ['You', '64'], ['Up', '62'], ['Never', '60'], ['Gonna', '59'], ['Let', '55'], ['You', '54'], ['Mark', '54']]


#program when it is executed *Example 2* 

Enter your name = John
Enter your score = 68
Congratulations! You are position 2 on the score board.


#name_score after user input
name_score = [['Never', '69'], ['John', '67'], ['Gonna', '66'], ['Give', '65'], ['You', '64'], ['Up', '62'], ['Never', '60'], ['Gonna', '59'], ['Let', '55'], ['You', '54']]


#program when it is executed *Example 3*

Enter your name = Bob
Enter your score = 40
Sorry, you did not make it into the score board.


#name_score after user input
name_score = [['Never', '69'], ['Gonna', '66'], ['Give', '65'], ['You', '64'], ['Up', '62'], ['Never', '60'], ['Gonna', '59'], ['Let', '55'], ['You', '54'], ['Down', '53']]

本质上，程序会用name_score的分数检查你的分数，如果你的分数是65 ，你将在第 4 位结束，之后的分数必须向下移动 1，用['Down', '53']出计分板。

Answer 1

首先，标准库中有一些工具对类似问题很有用，但我不知道如何让它们在这里工作：

• deque基本上是一个长度有限的列表，但如果它已经满了，它不会让你插入
• bisect_right可让您在排序列表中找到应插入新元素的点，但它似乎不支持反向排序列表

所以我写了一个函数place()来查找分数的位置，然后只需要list.insert()然后list.pop()来删除最后一个项目。 如果place()在没有匹配的情况下到达列表的末尾，则会出错。

旁注：我不知道你为什么将数字存储为字符串，所以我在这个例子中将它们设为整数。 我还缩短了示例记分板以提高可读性，并将项目元组制作为元组，因为这正是元组的用途。

scoreboard_example = [
    ('A', 69),
    ('B', 66),
    ('C', 65),
    ('D', 64),
    ('E', 62)]

def place(score, scoreboard):
    for i, (_name, existing) in enumerate(scoreboard):
        if existing < score:
            return i
    else:  # no break
        raise ValueError('did not place')

for test in ('Mark', 64), ('John', 68), ('Bob', 40):
    s = scoreboard_example.copy()
    try:
        position = place(test[1], s)
    except ValueError:
        print('Sorry, you did not make it into the score board.')
    else:
        print(f'Congratulations! You are position {position} on the score board.')
        s.insert(position, test)
        s.pop()
    print(s)
    print()

输出：

Congratulations! You are position 5 on the score board.
[('A', 69), ('B', 66), ('C', 65), ('D', 64), ('Mark', 64)]

Congratulations! You are position 2 on the score board.
[('A', 69), ('John', 68), ('B', 66), ('C', 65), ('D', 64)]

Sorry, you did not make it into the score board.
[('A', 69), ('B', 66), ('C', 65), ('D', 64), ('E', 62)]