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  • 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',}
    #
    #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)
    
    #
    # 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)
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  • 原文地址:https://www.cnblogs.com/aj-AJ/p/10798599.html
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