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HomeBackend DevelopmentPython TutorialThree methods for deep and shallow copying of python3 lists

This article mainly provides an in-depth analysis of the three methods of deep and shallow copying of python3 lists. It has certain reference value. Interested friends can refer to it

# Auther: Aaron Fan

names = ["aaron", "alex", "james", "meihengfan"]

#复制一份列表

#浅复制 (注意,这只是一个浅复制,只能复制第一层列表里面的东西,如果列表里面还有一层列表,那么那一层的列表只是把物理地址指向过去了,但是并没有复制过来)
#在day2第9个视频,有详细讲这个浅复制的作用,这里不再详细注释

person = ["name", ["saving", 100]]

'''
浅复制的方法有3种:
p1 = person.copy()
p1 = person[:]
p1 = list(person)
'''

p1 = person[:]
p2 = person[:]
print(p1)
print(p2)


p1[0] = "alex"
p2[0] = "fengjie"
print(p1)
print(p2)

#注意第二层列别中的值同时变了,这里联合账号来理解浅复制的作用
p1[1][1] = 50
print(p1)
print(p2)


#深复制(这种复制属于完完全全的复制,可以把列表里面的列表也复制过来,而不是仅仅只是指向一个地址过去)
import copy
names2 = copy.deepcopy(names)

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