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HDU 5416 CRB and Tree (樹形dp)

code
import copy
 
age = 19
print(f'first:{id(age)}')
age = 20
print(f'second:{id(age)}')
 
 
l1 = ['a', 'b', 'c', ['d', 'e', 'f']]
l2 = l1
 
 
print("*"*25,"賦值","*"*25)
l1.append('g')
print("l1:",l1)
print("l2:",l2)
 
 
l1 = ['a', 'b', 'c', ['d', 'e', 'f']]
l2 = copy.copy(l1)
 
 
print("*"*25,"淺拷貝-修改不可變元素
","*"*25) l1.append('g') print("l1:",l1) print("l2:",l2) print("*"*25,"淺拷貝-修改可變元素","*"*25) l1[3].append('g') print("l1:",l1) print("l2:",l2) l1 = ['a', 'b', 'c', ['d', 'e', 'f']] l2 = copy.deepcopy(l1) print("*"*25,"深拷貝-修改不可變元素","*"*25) l1.append('g') print("l1:",l1) print("l2:",l2) print(
"*"*25,"深拷貝-修改可變元素","*"*25) l1[3].append('g') print("l1:",l1) print("l2:",l2)
Outputs
macname@MacdeMacBook-Pro py % python3 cccccc.py
first:4525530480
second:4525530512
************************* 賦值 *************************
l1: ['a', 'b', 'c', ['d', 'e', 'f'], 'g']
l2: ['a', 'b', 'c', ['d', 'e', '
f'], 'g'] ************************* 淺拷貝-修改不可變元素 ************************* l1: ['a', 'b', 'c', ['d', 'e', 'f'], 'g'] l2: ['a', 'b', 'c', ['d', 'e', 'f']] ************************* 淺拷貝-修改可變元素 ************************* l1: ['a', 'b', 'c', ['d', 'e', 'f', 'g'], 'g'] l2: ['a', 'b', 'c', ['d', 'e', 'f', 'g']] ************************* 深拷貝-修改不可變元素 ************************* l1: ['a', 'b', 'c', ['d', 'e', 'f'], 'g'] l2: ['a', 'b', 'c', ['d', 'e', 'f']] ************************* 深拷貝-修改可變元素 ************************* l1: ['a', 'b', 'c', ['d', 'e', 'f', 'g'], 'g'] l2: ['a', 'b', 'c', ['d', 'e', 'f']] macname@MacdeMacBook-Pro py %