8-10: python crash课程中未变的魔术师

Question

我自己为这个任务编写了代码，如下所示：

def showmagicians(magician_names):
    for name in magician_names:
        print(name)

def make_great(magician_names):
    the_greats = []
    **for name in magician_names:**
        the_great = name +'_the_great'
        pop_name = magician_names.pop()
        the_greats.append(the_great)
    for the_great in the_greats:
        magician_names.append(the_great)
    return magician_names

magician_names = ['harry','david']
showmagicians(magician_names)
make_great(magician_names)
print(magician_names)

**Output:
harry
david
['harry', 'harry_the_great']**

我没有在‘make_great function’中使用'while‘语句，而是使用了'for’语句，并且输出是错误的。但我看不出这两者之间有什么区别。

该任务要求我们输出带有'the great‘后缀的'magician_names’。这本书提供的代码在这里列出：https://ehmatthes.github.io/pcc/solutions/chapter_8.html#8-6-city-names谁能告诉我有什么区别？

Answer 1

您正在magician_names上迭代，因此向前移动和 pop (删除项)，因此向后移动

在harry

• pop上，删除david

• cursor列表是['harry', 'david']游标，因此
• 没有其他地方可移动，您只需在harry

上迭代

让您的方法make_great返回the_greats列表，并将其赋给主代码中的一个变量，这样就很好了

def make_great(magician_names):
    the_greats = []
    for name in magician_names:
        the_great = name + '_the_great'
        the_greats.append(the_great)
    return the_greats


magician_names = ['harry', 'david']
print(magician_names)  # ['harry', 'david']
magician_names = make_great(magician_names)
print(magician_names)  # ['harry_the_great', 'david_the_great']

列表理解版本

def make_great(magician_names):
    return [name + '_the_great' for name in magician_names]