python-集合

#集合，天生可以去重,集合也是用{}来表示，集合没有k-v
#集合是无序的
#
l=[1,1,2,2,3,3]
res = set(l)
#l = list(res)
res.add(3)
print(res)

jihe = set()#定义一个空的集合
xingneng=['tanailing','yangfang','liurongxin']
zdh =['tanailing','yangfang','liurongxin','xiaojun','hailong']
xingneng = set(xingneng)
zdh = set(zdh)
res = xingneng.intersection(zdh)#取交集
res = xingneng & zdh #也是取交集
print(res)

res2 = xingneng.union(zdh) #取并集，把两个集合合并到一起并去重
#res2 = xingneng|zdh  #也是取并集
print(res2)

#差集
res3 = xingneng.difference(zdh)
res3 = zdh.difference(xingneng)
#res3 = xingneng - zdh
print(res3)

#对称差集
res4 = xingneng.symmetric_difference(zdh)
res4 = xingneng^zdh

print(res4)


import string
l1 = set(string.ascii_lowercase)
print("'aaaaaaaaaaaaaaaaaaaaaaa'+")
print(l1)
l2 = {'a','b','c'}
print(l2.issubset(l1))
print(l2)
print(l1.issuperset(l2))
print(l1.isdisjoint(l2))#是否有交集,有交集返回False，无交集返回True


l2.add('s')#添加元素
l2.remove('a')#删除指定的元素
l2.pop()#随机删除一个元素