集合 相关 深浅copy

''
集合：可变的数据类型，他里面的元素必须是不可变的数据类型，无序，不重复。
     {}
'''
# set1 = set({1,2,3})
# set2 = {1,2,3,[2,3],{'name':'alex'}}  # 错的  集合和字典是可变数据类型
# print(set1)
# print(set2)
# set1 = {'alex','wusir','ritian','egon','barry',}
#增
#add
# set1.add('女神')
# print(set1)
#update   #迭代增加
# set1.update('abc')
# print(set1)
#删除
 
# set1.pop()  # 随机删除
# print(set1.pop())  # 有返回值
# print(set1)
 
# set1.remove('alex')  # 按元素
# print(set1)
 
#空字典{}    空集合set()
# set1.clear()
# print(set1)  # set()
 
# del set1   #删除集合
# print(set1)
 
#查
# for i in set1:
#     print(i)
 
# set1 = {1,2,3,4,5}
# set2 = {4,5,6,7,8}
# set3 = set1 & set2     #交集
# print(set3)  # {4, 5}
# print(set1.intersection(set2))  # {4, 5}
 
# set1 = {1,2,3,4,5}
# set2 = {4,5,6,7,8}
# print(set1 | set2)  # {1, 2, 3, 4, 5, 6, 7,8}      #并集
# print(set2.union(set1))  # {1, 2, 3, 4, 5, 6, 7}
 
# set1 = {1,2,3,4,5}
# set2 = {4,5,6,7,8}
# print(set1 ^ set2)  # {1, 2, 3, 6, 7, 8}
# print(set1.symmetric_difference(set2))  # {1, 2, 3, 6, 7, 8}
 
# set1 = {1,2,3,4,5}
# set2 = {4,5,6,7,8}
# print(set1 - set2)  # {1, 2, 3}     #差集
# #set1独有的
# print(set1.difference(set2))  # {1, 2, 3}
 
# set1 = {1,2,3,}
# set2 = {1,2,3,4,5,6}
#
# print(set1 < set2)
# print(set1.issubset(set2))  # 这两个相同，都是说明set1是set2子集。
 
# print(set2 > set1)
# print(set2.issuperset(set1))  # 这两个相同，都是说明set2是set1超集。
 
#去重
# li = [1,2,33,33,2,1,4,5,6,6]
# set1 = set(li)
# # print(set1)
# li = list(set1)
# print(li)
# s1 = {1,2,3}
# print(s1,type(s1))
 
# s = frozenset('barry')
# print(s,type(s))
# for i in s:
#     print(i)

深浅copy

# 赋值运算
# l1 = [1,2,3]
# l2 = l1
# l1.append('a')
# print(l1,l2)
 
#copy
# l1 = [1,2,3]
# l2 = l1.copy()
# print(l1,l2)
# print(id(l1),id(l2))
# l2.append('a')
# print(l1,l2)
 
# l1 = [1,2,[4,5,6],3]
# l2 = l1.copy()
#
# print(l1,id(l1))
# print(l2,id(l2))
# l1.append('a')
# print(l1,l2)
# l1[2].append('a')
# print(l1,l2)
# print(id(l1[2]))
# print(id(l2[2]))
import copy
# l1 = [1,2,[4,5,6],3]
# l2 = copy.deepcopy(l1)
# print(l1,id(l1))
# print(l2,id(l2))
# l1[2].append('a')
# print(l1,l2)
 
# l1 = [1,[1],2,3,4]
# l2 = l1
# # l1[1].append('a')
# # l2 的结果是什么?
#
#
# print(l1,id(l1))
# print(l2,id(l2))
# print(l1[1] is l2[1])

enumerate 用法

# li = ['alex','taibai','wusir','egon']
# for i in li:
#     print(li.index(i),i)
 
# for index,i in enumerate(li,1):
#     print(index,i)