字符串、组合数据类型练习

字符串练习：

http://news.gzcc.cn/html/2017/xiaoyuanxinwen_1027/8443.html

取得校园新闻的编号

str='http://news.gzcc.cn/html/2017/xiaoyuanxinwen_1027/8443.html'
print(str[-14:-5])

　　

https://docs.python.org/3/library/turtle.html

产生python文档的网址

str="https://docs.python.org/3/library/"+"turtle"+".html"
print(str)

　　

http://news.gzcc.cn/html/xiaoyuanxinwen/4.html

产生校园新闻的一系列新闻页网址

for i in range(5):
    print('http://news.gzcc.cn/html/xiaoyuanxinwen/{ }.html'.format(i))

　　

练习字符串内建函数：strip,lstrip,rstrip,split,count

用函数得到校园新闻编号

str='http://news.gzcc.cn/html/2017/xiaoyuanxinwen_1027/8443.html'
print(str.strip('.html').split('_')[1])

　　

用函数统计一歌词中单词出现的次数

str='''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 ooooh 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.'''
print(str.count('big'))

　　

将字符串分解成一个个的单词。

str='long time no see'
print(str.split())

2.组合数据类型练习

分别定义字符串，列表，元组，字典，集合，并进行遍历。

字符串

string='Michael'
for str in string:
    print(str)

列表

list=['Michael','Tracy','Bob','wangwu']
for l in list:
    print(l)

元祖

tuple=('Michael','Tracy','Bob','wangwu')
for tup in tuple:
    print(tup)

字典

dict = dict(zip('python', '123456'))
for i in dict:
    print(i)
for i in dict.keys():
    print(i)
for i in dict.values():
    print(i)
for i in dict.items():
    print(i)

集合

set={'Michael','Tracy','Bob','wangwu'}
for i in set:
        print(i)

　　

总结列表，元组，字典，集合的联系与区别。