错误是因为只能将列表（而不是“非类型”）连接到列表

Question

我想反转Jamies_列表和Drews列表，应该先在列表中，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()是一种就地操作。它不会返回反向列表，而是返回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))

否则

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))

否则

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))