Question

如果我有这样的字典：

dict = {'a': ['Menny','Adam'], 'b': ['Steff','Bentz', 'Arik'], 'c': ['Menny','Stephonich', 'Marry', 'Kenny', 'Mike', 'Pring']

等等。

如果我想检查其键中的两个列表之间是否存在一些共同的值。我该怎么办？

例如，在a和c中有“Menny”......

Answer 1

我会构建一个反向索引：

from collections import defaultdict

reverse = defaultdict(set)

for key, values in dct.items():
    for value in values:
        reverse[value].add(key)

现在您可以找到密钥之间共享的任何值：

for value, keys in reverse.items():
    if len(keys) > 1:
        print(value, keys)

演示：

>>> from collections import defaultdict
>>> dct = {'a': ['Menny','Adam'], 'b': ['Steff','Bentz', 'Arik'], 'c': ['Menny','Stephonich', 'Marry', 'Kenny', 'Mike', 'Pring']}
>>> reverse = defaultdict(set)
>>> for key, values in dct.items():
...     for value in values:
...         reverse[value].add(key)
... 
>>> for value, keys in reverse.items():
...     if len(keys) > 1:
...         print(value, keys)
... 
Menny {'c', 'a'}

如果要测试两个键，请使用：

def check_keys(dct, key1, key2):
    return not set(dct[key1]).isdisjoint(dct[key2])

演示：

>>> check_keys(dct, 'a', 'c')
True
>>> check_keys(dct, 'a', 'b')
False

或者，返回常用值：

def values_intersection(dct, key1, key2):
    return set(dct[key1]).intersection(dct[key2])

演示：

>>> values_intersection(dct, 'a', 'c')
{'Menny'}
>>> values_intersection(dct, 'a', 'b')
set()

Answer 2

def check(value, dictionary, keys):
    return all(value in dictionary[key] for key in keys)

演示：

>>> def check(value, dictionary, keys):
        return all(value in dictionary[key] for key in keys)

>>> d= {'a': ['Menny','Adam'], 'b': ['Steff','Bentz', 'Arik'], 'c': ['Menny','Stephonich', 'Marry', 'Kenny', 'Mike', 'Pring']}
>>> check('Menny', d, ['a', 'b'])
False
>>> check('Menny', d, ['a', 'c'])
True
>>>

如果您想拥有共享值的键：

def check(value, d):
    keys_found = []
    for k,v in d.items():
        if value in v:
            keys_found.append(k)
    return keys_found

演示：

>>> def check(value, d):
    keys_found = []
    for k,v in d.items():
        if value in v:
            keys_found.append(k)
    return keys_found

>>> check('Menny', d)
['c', 'a']

在Python中检查值和键

2 个答案: