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09-python浅拷贝和深拷贝

09-python浅拷贝和深拷贝

作者: weyan | 来源:发表于2018-01-19 10:25 被阅读0次
#浅拷贝:只拷贝第一层,相当于把第一层克隆了一份,而["易辰","子涵"]这个拷贝的是内存地址,所以当第二层元素改变时所有跟着改变;如果我们想要完整的拷贝一份,就用深拷贝。
'''names = ["Zhansan","Lishi",["易辰","子涵"],"Wangwu","Zhaoliu"]
names2 = names.copy()
names2[-1] = "麻子"
names[2][0] = "yichen"
print(names)
print(names2)
'''

#深拷贝:完全拷贝,和原来的列表完全是独立的
#import copy

#names = ["Zhansan","Lishi",["易辰","子涵"],"Wangwu","Zhaoliu"]
#names2 = copy.copy(names)#浅拷贝
#names2 = copy.deepcopy(names)
#names2[-1] = "麻子"
#names[2][0] = "yichen"
#print(names)
#print(names2)


#for循环
names = ["Zhansan","Lishi",["易辰","子涵"],"Wangwu","Zhaoliu"]
print(names[0:-1:2])#切片,步长为2,如果是0和-1可以省略
print(names[::2])
for i in names:
    print(i)#把列表中的元素全部打印出来

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