缩进错误While循环在Python

Question

我有以下的功能，我收到Indentation Error每当我尝试运行它：

def fib(n):  
    # write Fibonacci series up to n 
    """Print a Fibonacci series up to n.""" 
a, b = 0, 1 
while a < n: 
print a 
a, b = b, a+b 
# Now call the function we just defined: 
fib(2000) 

错误消息：

print a 
     ^
IndentationError: expected an indented block 

如何解决的IndentationError Python中的错误？

Answer 1

您需要正确缩进代码。就像其他语言使用括号一样，Python使用缩进：

def fib(n):  
    # write Fibonacci series up to n 
    """Print a Fibonacci series up to n.""" 
    a, b = 0, 1 

    while a < n: 
     print a 
     a, b = b, a+b 

Answer 2

您必须添加空格。你的鳕鱼必须是这样的：

def fib(n):  
# write Fibonacci series up to n 
"""Print a Fibonacci series up to n.""" 
     a, b = 0, 1 

     while a < n: 

      print a 

      a, b = b, a+b 

# Now call the function we just defined: 
fib(2000)