使用python插入方法挑战

Question

我正在尝试一些 python 列表练习问题。我试图在索引“-1”处插入一个新名称 mike，但在将输出打印到屏幕时，我注意到它默认为晚餐列表中的另一个位置（索引 (-2)）。

dinner = ['yemi', 'bimpe', 'kola', 'kunle', 'bola', 'shola', 'ola']

invite = f"{dinner[0].title()}, would you be available to attend our dinner party?"
print(invite)

invite = f"{dinner[-1].title()}, would you be available to attend our dinner party?"
print(invite)

invite = f"{dinner[-3].title()}, would you be available to attend our dinner party?"
print(invite)

invite = f"{dinner[3].title()}, would you be available to attend our dinner party?"
print(invite)

invite = f"{dinner[1].title()}, would you be available to attend our dinner party?"
print(invite)

not_coming = f"{dinner[0].title()} said she can't make the dinner party tonight and has to be swapped with {dinner[1].title()}"
print(not_coming)

not_coming = f"{dinner[-1].title()} said she can't make the dinner party tonight and has to be swapped with {dinner[-2].title()}"
print(not_coming)

dinner.insert(0, "kingsley")
print(dinner)

dinner.insert(-1, "mike")
print(dinner)

为什么会这样？

列表名称是“晚餐”

Answer 1

list.insert 状态的文档

在给定位置插入一个项目。第一个参数是要插入的元素的索引

所以如果你使用索引-1，它会在最后一个之前插入

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要插入最后一个，请使用其中之一

dinner.insert(len(dinner), "mike")
dinner.append("mike")