<span style="font-size:18px;">>>> lang = "python"
>>> if lang == "C":
...     print "C language"
... elif lang == "Java":
...     print "Java language"
... else:
...     print "Python language"
... 
Python language
>>> </span><span style="font-size:14px;">
</span>

循环语句

<span style="font-size:18px;">>>> count = 0
>>> while(count < 9):
...     print 'the index is:', count
...     count += 1
... 
the index is: 0
the index is: 1
the index is: 2
the index is: 3
the index is: 4
the index is: 5
the index is: 6
the index is: 7
the index is: 8
>>> </span><span style="font-size:14px;">
</span>

<span style="font-size:18px;">>>> game = ['LOL', 'GT', 'CSOL']
>>> for g in game:
...     print 'you play %s' % game
... 
you play ['LOL', 'GT', 'CSOL']
you play ['LOL', 'GT', 'CSOL']
you play ['LOL', 'GT', 'CSOL']

>>> for index in range(len(game)):
...     print 'you play %s' % game[index]
... 
you play LOL
you play GT
you play CSOL
>>> </span><span style="font-size:14px;">
</span>

<span style="font-size:18px;">def showMaxFactor(num):
        count = num/2
        while count > 1:
                if num % count == 0:
                        print 'largest factor of %d is %d' % (num, count)
                        break;
                count -= 1
        else:
                print num, 'is prime'

for eachNum in range(10,21):
        showMaxFactor(eachNum)</span><span style="font-size:14px;">
</span>

<span style="font-size:18px;">linux-ne7w:~/python> python maxFact.py 
largest factor of 10 is 5
11 is prime
largest factor of 12 is 6
13 is prime
largest factor of 14 is 7
largest factor of 15 is 5
largest factor of 16 is 8
17 is prime
largest factor of 18 is 9
19 is prime
largest factor of 20 is 10</span><span style="font-size:14px;">
</span>

迭代器

• 为什么要迭代器：
• 提供了可扩展的迭代器接口
• 对列表迭代提供了性能上的增强
• 在字典迭代中性能提升
• 创建真正的迭代接口，而不是原来的随机对象访问
• 与所有已经存在的用户定义的类以及扩展的模拟序列和映射的对象向后兼容
• 迭代非序列集合时，可以创建更简洁可读的代码

<span style="font-size:18px;">>>> t = (123, 'text', 66.66)
>>> t
(123, 'text', 66.66)
>>> i = iter(t)
>>> i.next()
123
>>> i.next()
'text'
>>> i.next()
66.66
>>> i.next()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
StopIteration
>>> </span><span style="font-size:14px;">
</span>

<span style="font-size:18px;">>>> f = open('text.txt', 'r')
>>> for eachLine in f:
...      print eachLine,
... 
This is just for a test

everyone should learn programming, programming teach you thinking.

forget my poor english.haha.</span><span style="font-size:14px;">
</span>

列表解析

<span style="font-size:18px;">[x ** 2 for x in range(6)]
[0, 1, 4, 9, 16, 25]
>>> seq = [11, 10, 89, 32, 43, 22, 55, 23, 21, 32]
>>> [x for x in seq if x % 2]
[11, 89, 43, 55, 23, 21]</span>

<span style="font-size:18px;">>>> [(x+1,y+1) for x in range(3) for y in range(4)]
[(1, 1), (1, 2), (1, 3), (1, 4), (2, 1), (2, 2), (2, 3), (2, 4), (3, 1), (3, 2), (3, 3), (3, 4)]
>>> </span><span style="font-size:14px;">
</span>

生成器表达式