Python编程 从入门到实践 第四章 作业参考答案 （部分）

4-2 动物

animals = ["dog","cat","panda","squirrel"] for a in animals: print(a.title()) for a in animals: print("A",a,"could be so cute!") print("Any of these could be a cute icon!") Dog Cat Panda Squirrel A dog could be so cute! A cat could be so cute! A panda could be so cute! A squirrel could be so cute! Any of these could be a cute icon!

4-5 一百万

million = list(range(1,1000001)) print(min(million)) print(max(million)) print(sum(million)) 1 1000000 500000500000

4-6 4-7 奇数 3的倍数

odds = list(range(1,21,2)) for odd in odds: print(odd) print('---------') times3 = list(range(3,31,3)) for t3 in times3: print(t3) 1 3 5 7 9 11 13 15 17 19 --------- 3 6 9 12 15 18 21 24 27 30

4-9 列表解析

mylist = [num**3 for num in range(1,11)] print(mylist) [1, 8, 27, 64, 125, 216, 343, 512, 729, 1000]

4-10 切片

animals = ["dog","cat","panda","squirrel"] print("The first three items:",animals[:3]) print("Three items from the middle of the list are:",animals[1:4]) print("The last three items are:",animals[-3:]) The first three items: ['dog', 'cat', 'panda'] Three items from the middle of the list are: ['cat', 'panda', 'squirrel'] The last three items are: ['cat', 'panda', 'squirrel']

4-13 自助餐，略

（元组元素不能被修改）