快速找到多个字典的公共键(key)

'''
快速找到多个字典的公共键(key)
'''
from functools import reduce
from random import randint,sample
#随机取样 在'abcdefg'七个字母中随机取3个
s1 = sample('abcdefg',3)
print(s1)
#随机取样 在'abcdefg'七个字母中随机取3-7个
s2 = sample('abcdefg',randint(3,7))
dict1 = {x:randint(1,4) for x in sample('abcdefg',randint(3,7))}
dict2 = {x:randint(1,4) for x in sample('abcdefg',randint(3,7))}
dict3 = {x:randint(1,4) for x in sample('abcdefg',randint(3,7))}
print(dict1)
print(dict2)
print(dict3)
res=[]
#遍历出公共键
for x in dict1:
    if x in dict2 and x in dict3:
        res.append(x)

print(res)

#使用集合找出公共键  dict.keys为字典的K
print(dict1.keys())

res1 = dict1.keys() & dict2.keys() & dict3.keys()
print(res1)


#使用map与reduce计算N条集合的公共键
dictmap = map(dict.keys,[dict1,dict2,dict3])
print(list(dictmap))
res2 = reduce(lambda x,y : x & y ,map(dict.keys,[dict1,dict2,dict3]))
print(res2)