python学习之while语句

c_u_c_u

while语句在一个条件为真的情况下，while语句允许你重复执行一块语句。直接看例子：

1. #!/usr/bin/python
   
2. # Filename: while.py
   
3. 
   
4. number = 23
   
5. running = True
   
6. 
   
7. while running:
   
8.     guess = int(raw_input('Enter an integer : '))
   
9. 
   
10.     if guess == number:
    
11.         print 'Congratulations, you guessed it.'
    
12.         running = False # this causes the while loop to stop
    
13.     elif guess < number:
    
14.         print 'No, it is a little higher than that'
    
15.     else:
    
16.         print 'No, it is a little lower than that'
    
17. else:
    
18.     print 'The while loop is over.'
    
19.     # Do anything else you want to do here
    
20. 
    
21. print 'Done'
    

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当输入23时，程序执行done,结束，否则一直在循环（当然输入非整数时语法错误，程序会跳出的）。

运行结果：

1. $ python while.py
   
2. Enter an integer : 50
   
3. No, it is a little lower than that.
   
4. Enter an integer : 22
   
5. No, it is a little higher than that.
   
6. Enter an integer : 23
   
7. Congratulations, you guessed it.
   
8. The while loop is over.
   
9. Done

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//这里要说明的是python语言对空格要求的很严格，必须是对应的，否则语法是不正确的。

donotblock

好吧，我承认你在教没接触过编程的同学...

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