1.实例: 下载一首英文的歌词或文章，将所有,.？！等替换为空格，将所有大写转换为小写，统计某几个单词出现的次数，分隔出一个一个的单词。

s='''I'm a big big girl !

In a big big world !

It's not a big big thing if you leave me.

But I do do feel.

That I too too will miss you much.

Miss you much !

I can see the first leaf falling.

It's all yellow and nice.

It's so very cold outside.

Like the way I'm feeling inside.

I'm a big big girl !

In a big big world !

It's not a big big thing if you leave me.

But I do do feel.

That I too too will miss you much.

Miss you much !

Outside it's now raining.

And tears are falling from my eyes.

Why did it have to happen ?

Why did it all have to end ?

I'm a big big girl !

In a big big world !

It's not a big big thing if you leave me.

But I do do feel.

That I too too will miss you much.

Miss you much !

I have your arms around me warm like fire.

But when I open my eyes.

You're gone !

I'm a big big girl !

In a big big world !

It's not a big big thing if you leave me.

But I do do feel.

That I too too will miss you much.

Miss you much !

I'm a big big girl !

In a big big world !

It's not a big big thing if you leave me.

But I do feel that will miss you much !

Miss you much ! '''

s=s.lower()

s=s.replace('.',' ')

s=s.replace('!',' ')

s=s.split(' ')

print(s)

print('I出现的次数:',d.count('I'))

print('big出现的次数:',d.count('big'))

 

2. 列表实例：由字符串创建一个作业评分列表，做增删改查询统计遍历操作。例如，查询第一个3分的下标，统计1分的同学有多少个，3分的同学有多少个等。

s=list('345665435643786543')

print(s)

print("3分的人数:",s.count('3'))

print("5分的人数:",s.count('5'))

s.append('8')

print('增加一个同学的成绩为8:',s)

print('修改下标为6的同学的分数为7:',s)

3，简要描述列表与元组的异同

 答：列表list是处理一组有序项目的数据结构，可以在一个列表中存储一个序列的项目。元组和列表十分相似，不过元组是不可变的，即不能修改元组，元组通过圆括号中用逗号分隔的项目定义。