将两个列表连接成一个而不重复

Question

我如何一起加入2个列表？

让我们说：

list1 = ['hi', 'state', 'California', 'usa']
list2 = ['moon', 'sun', 'hi', 'flower']

并且输出会将单词连接在一起，排除包含相同单词的单词，例如'hi hi'，如下所示：

['hi moon', 'hi sun', ' hi flower', 'state moon', 'state hi', 'state flower'] ...eetc..

Answer 1

使用itertools.product()，然后过滤掉相同的任何对：

from itertools import product

[' '.join([a, b]) for a, b in product(list1, list2) if a != b]

演示：

>>> from pprint import pprint
>>> from itertools import product
>>> list1 = ['hi', 'state', 'California', 'usa']
>>> list2 = ['moon', 'sun', 'hi', 'flower']
>>> [' '.join([a, b]) for a, b in product(list1, list2) if a != b]
['hi moon', 'hi sun', 'hi flower', 'state moon', 'state sun', 'state hi', 'state flower', 'California moon', 'California sun', 'California hi', 'California flower', 'usa moon', 'usa sun', 'usa hi', 'usa flower']
>>> pprint(_)
['hi moon',
 'hi sun',
 'hi flower',
 'state moon',
 'state sun',
 'state hi',
 'state flower',
 'California moon',
 'California sun',
 'California hi',
 'California flower',
 'usa moon',
 'usa sun',
 'usa hi',
 'usa flower']

Answer 2

迭代列表解析中的每个列表。在这种情况下，我并不需要product：

>>> list1 = ['hi', 'state', 'California', 'usa']
>>> list2 = ['moon', 'sun', 'hi', 'flower']
>>> [a+' '+b for a in list1 for b in list2 if a != b]
['hi moon', 'hi sun', 'hi flower', 'state moon', 'state sun', 'state hi', 'state flower', 'California moon', 'California sun', 'California hi', 'California flower', 'usa moon', 'usa sun', 'usa hi', 'usa flower']

这相当于较长的形式：

>>> L = []
>>> for a in list1:
...     for b in list2:
...         if a != b:
...             L.append(a+' '+b)
...             
>>> L
['hi moon', 'hi sun', 'hi flower', 'state moon', 'state sun', 'state hi', 'state flower', 'California moon', 'California sun', 'California hi', 'California flower', 'usa moon', 'usa sun', 'usa hi', 'usa flower']