集合的创建

s = set()
print(s, type(s))
s = {1,2,3,4,1,2} # 集合的元素是不重复的
print(s,type(set))
s = set([1,2,3,1]) # list-->set
print(s)
s = set((1,2,3)) # tuple-->set
s = set('123') # str-->set
print(s)
s = set({
1:'a',
'a':2
}) # dict-->set
print(s)

in

print(1 in s)

len

print(len(s))
print(max({1,2,3,4,5,6}))
print(min({1,2,3,4,5,6}))

del s

print(s[1]) # 不支持

集合的遍历

for i in s:
print(i)

集合常用的方法

s.remove('a')
print(s)
s.update({2,3,4,5,6,7,87,4,2,4})
print(s)
s.add(9)
print(s)
s.add(1)
print(s)
print(s)

交集 并集

s2 = {5,6,7,8,9}
print(s2)
print(s & s2)
print(s | s2)

列表去重

score = [80,70,60,50,60,70,80]
s = set(score)
print(s)
d ={}

统计各个分数都有几个学生

for i in s:
t = score.count(i)
print('得分为%d的学生有%d个人' %(i,t))
d[i] = t
for k,v in d.items():
print('得分为%d的学生有%d个人' %(k,v))