* while 循环
# while expression:
statement(s)
猜数字
#!/usr/bin/env python
# -*- coding: utf-8 -*-
import random
number = random.randint(1,101)
guess=0
while True:
num_input=raw_input("please input one integer that is in 1 to 100:")
guess +=1 #统计猜的次数
if not num_input.isdigit():
print "please input integer."
elif int(num_input)<0 or int(num_input)>100:
print "The number should in 0 to 100."
else:
if number == int(num_input):
print "Ok,you are good. It is only %d, then you success."%guess
break #猜对了就跳出循环
elif number>int(num_input):
print "Your number is more less."
elif number<int(num_input):
print "Your number is bigger"
else:
print "something is wrong."
[email protected]:/var/www/erp-yejian# python test.py
please input one integer that is in 1 to 100:50
Your number is more less.
please input one integer that is in 1 to 100:75
Your number is bigger
please input one integer that is in 1 to 100:65
Your number is bigger
please input one integer that is in 1 to 100:55
Your number is more less.
please input one integer that is in 1 to 100:60
Your number is more less.
please input one integer that is in 1 to 100:63
Your number is more less.
please input one integer that is in 1 to 100:64
Ok,you are good. It is only 7, then you success.
# break 和 continue
break:跳出循环
continue:跳过本次循环进入下一次循环
这两个都是在循环体中控制循环流程
# while ... else...
当运行到else时，就出了循环体
#!/usr/bin/env python
# -*- coding: utf-8 -*-
count=0
while count<3:
print count," is less than 3"
count+=1
else:
print count," is not less than 3"
[email protected]:/var/www/erp-yejian# python test.py
0 is less than 3
1 is less than 3
2 is less than 3
3 is not less than 3
* 强大的for
>>> mystr="hello"
>>> for i in mystr:
... print i,
...
h e l l o
一个字母一个字母打印出来
>>> mylist=[11,‘good‘,22]
>>> for i in mylist:
... print i,
...
11 good 22
遍历列表
>>> mytuple=(1,‘ss‘,2)
>>> for i in mytuple:
... print i,
...
1 ss 2
遍历元组
>>> mydict={‘first‘:"good","second":"better"}
>>> for i in mydict.values():
... print i,
...
better good
遍历字典
>>> myset={‘good‘,‘better‘}
>>> for i in myset:
... print i,
...
better good
遍历集合
>>> for i in range(2,8):
... print i,
...
2 3 4 5 6 7
遍历range产生的列表
>>> [i for i in range(3,9) if i%2==0]
Out[2]: [4, 6, 8]
列表解析中遍历
>>> str1
Out[16]: ‘hello‘
>>> str2
Out[17]: ‘world‘
>>> for x,y in zip(str1,str2):
... print x,y
...
h w
e o
l r
l l
o d
和zip函数使用
* 迭代
# iter
>>> mylist
Out[42]: [‘name‘, 88]
>>> list_iter=iter(mylist)
>>> while True:
... print list_iter.next()
...
name
88
一个一个的输出