集合运算

s = set("hello")
print(s)

或

s = {1,2,3,4,3}
print(s)

#增加元素
s = {1,2,3,4,5}
s.add("reese")
print(s)

#输出{1, 2, 3, 4, 5, 'reese'}

#清空
s = {1,2,3,4,5}
s.clear()
print(s)

#输出结果：set()

#随机删除
s = {"re",3,4,5,6,8}
s.pop()
print(s)

#输出结果：{4, 5, 6, 8, 're'}

#指定删除
s = {1,2,3,4,5,7,"neo"}
s.remove("neo")
print(s)

#输出结果：{1, 2, 3, 4, 5, 7}

#指定删除，删除元素不存在不会报错
s1 = {1, 2, 3, 4, 5, 7, "neo"}
s1.discard("neo")
print(s1)
s2 = {1, 2, 3, 4, 5, 7, "neo"}
s2.discard("neoll")
print(s2)

#输出结果：
{1, 2, 3, 4, 5, 7}
{1, 2, 3, 4, 5, 7, 'neo'}

s1 = {12, 34, 56, 123, 890}
s2 = {354, 45, 78, 34, 123, 90}
print(s1 & s2)
# 取交集
print(s1.intersection(s2))

#输出结果：
{34, 123}
{34, 123}

s1 = {"reese", 123, 567, 89}
s2 = {123, 89, 45, "neo"}
# 取并集
print(s1 | s2)
print(s1.union(s2))

#输出结果：
{'neo', 'reese', 45, 567, 89, 123}
{'neo', 'reese', 45, 567, 89, 123}

s1 = {"reese", 123, 567, 89}
s2 = {123, 89, 45, "neo"}
# 差集
print(s1 - s2)
print(s1.difference(s2))

#输出结果：
{'reese', 567}
{'reese', 567}

s1 = {"reese", 123, 567, 89}
s2 = {123, 89, 45, "neo"}
#交叉补集
print("交叉补集",s1^s2)
print("交叉补集",s1.symmetric_difference(s2))

#输出结果：
交叉补集 {'reese', 45, 'neo', 567}
交叉补集 {'reese', 45, 'neo', 567}

s1 = {1,2,3}
s2 = {4,5,6}
s3 = {2,7,0}
print(s1.isdisjoint(s2))
print(s1.isdisjoint(s3))

#输出结果：
True
False

s1 = {1,2,3}
s2 = {1,2,3,4}
print(s1.issubset(s2)) #s1 是 s2的子集

#输出结果：
True