Python自学：第七天作业解析-优快云博客

今天是Python自学的第七天，重点介绍了如何使用for循环和range函数来获取列表的索引。作业中要求通过编写代码实现这一功能，锻炼了初学者对循环控制的理解和应用。

1.请用代码实现

li = ["alex","eric","rain"]
#利用下划线将列表的每一个元素拼接成字符串
s = ""
for i in li:
    s = s + i + '_'
print(s[:-1])

2.利用for循环和range打印出下面列表的索引:

li = ["alex","wusir","ritian","barry","wenzhou"]

li = ["alex","wusir","ritian","barry","wenzhou"]
for i in range(len(li)):
    print(i)

4.利用for循环和range找出100以内所有的偶数并将这些偶数插入到一个新列表中

lst = []
for i in range(101):
    if i % 2 == 0:
        lst.append(i)
print(lst)

5有如下列表
li = [1,3,4,"alex",[3,7,8,"TaiBai"],5,"RiTian"]
循环打印列表中的每个元素,遇到列表则再循环打印出它里面的元素:
预期效果:
1
3
4
"alex"
3
7
8
"TaiBai"
5
ritian

li = [1,3,4,"alex",[3,7,8,"TaiBai"],5,"RiTian"]
for i in li:
    if type(i) == list:
        for el in i:
            if type(el) == int:
                print(el)
            else:
                print('"' + el + '"')
    elif type(i) == int:
        print(i)
    else:
        print('"' + i.lower() + '"')

6把班级学生数学考试成绩录入到一个列表中:并求平均值.要求:录入的时候要带着名字录入，例如:张三_44

li = []
while 1:
    stu = input("请输入你的名字和分数(格式:张三_44),输入Q退出:")
    if stu.lower() == 'q':
        break
    else:
        ret = stu.split('_')
        li.append(ret[1])
        
sum_num = 0
for i in li:
    sum_num = sum_num + int(i)
print(sum_num/len(li))