Python中的集合介绍

s = {1,2,3,1,2,3,4,5}
print(s)
print(type(s))
s1 = {1}
print(s1)
print(type(s1))

s2 = {}
print(type(s2))
s3 = set([])
print(s3)
print(type(s3))

li = [1,2,3,1,2,3]
print(list(set(li)))

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

for i in s:
  print(i,end='|')
for i,v in enumerate(s):
  print('index: %s,value: %s' %(i,v))

s = {6,7,8,9}
#增加一个元素
s.add(1)
print(s)

s.update({5,3,2})   ##使用update命令
print(s)

s.pop()
print(s)

s.remove(5)
print(s)

s = {1,2,3}
s2={2,3,4}

print('并集:',s1.union(s2))
print('并集:',s1|s2)

print('交集:',s1.intersection(s2))
print('交集:',s1&s2)

print('差集:',s1.difference(s2)) #s1-(s1&s2)
print('差集:',s2.difference(s1)) #s2-(s1&s2)

print('对等差分:',s2.symmetric_difference(s1))
print('对等差分:',s1^s2)

s3 = {1,2}
s4 = {1,2,3}
#s3是否为s4的超集
#超集:如果s3中的每一个元素都在集合s4中,且s4中可能包含s3中没有的元素,
#那么s4就是s3的一个超集
print(s3.issuperset(s4))
print(s4.issuperset(s3))
#s3是否为s4的子集
print(s3.issubset(s4))
#两个集和是不是 不相交
print(s3.isdisjoint(s4))

s = set([])
for i in range(int(input('N:'))):
  s.add(random.randint(1,1000))
print(s)
print(sorted(s))