错误来了，因为只能连接列表(而不是"NoneType")到列表

Question

我想反转Jamies_list，Drews列表应该先在其中，然后附加这两个列表，我想返回完整的列表。

def combine_lists(list1, list2):
# Generate a new list containing the elements of list2
# Followed by the elements of list1 in reverse order
return(list2+list1.reverse())

Jamies_list = ["Alice", "Cindy", "Bobby", "Jan", "Peter"]
Drews_list = ["Mike", "Carol", "Greg", "Marcia"]
print(combine_lists(Jamies_list, Drews_list))

Answer 1

.reverse()是一个就地操作。它不会返回反向列表，它返回None

使用sorted(list1, reverse=True)。

def combine_lists(list1, list2):
# Generate a new list containing the elements of list2
# Followed by the elements of list1 in reverse order
return(list2+sorted(list1, reverse=True))

Jamies_list = ["Alice", "Cindy", "Bobby", "Jan", "Peter"]
Drews_list = ["Mike", "Carol", "Greg", "Marcia"]
print(combine_lists(Jamies_list, Drews_list))

其他

def combine_lists(list1, list2):
# Generate a new list containing the elements of list2
# Followed by the elements of list1 in reverse order
list1.reverse()
return(list2+list1)

Jamies_list = ["Alice", "Cindy", "Bobby", "Jan", "Peter"]
Drews_list = ["Mike", "Carol", "Greg", "Marcia"]
print(combine_lists(Jamies_list, Drews_list))

其他

def combine_lists(list1, list2):
# Generate a new list containing the elements of list2
# Followed by the elements of list1 in reverse order
return list2 + list1[::-1]

Jamies_list = ["Alice", "Cindy", "Bobby", "Jan", "Peter"]
Drews_list = ["Mike", "Carol", "Greg", "Marcia"]
print(combine_lists(Jamies_list, Drews_list))

Answer 2

reverse((是Python编程语言中的一个内置方法，在适当的位置反转列表中的对象

您也可以使用print(list1.reverse(((进行检查。它将打印None。

因此建议使用return list2 + list1[::-1]