创建列表的有效方法:从类变量创建列表.(多个列表)

Question

哪个例子更快?

示例1

A = [] 
B = [] 
C = [] 
for i in range(x, y): 
A.append(obj[i].a) 
B.append(obj[i].b) 
C.append(obj[i].c) 

示例2

A = [obj[i].a for i in range(x, y)]
B = [obj[i].b for i in range(x, y)] 
C = [obj[i].c for i in range(x, y)] 

Answer 1

第一个:

• 复杂度为O(n)
• 复杂度第二种为O(3n)