How to make a reverse for loop in python?

Fredrik Lundh fredrik at pythonware.com
Sat Sep 20 12:37:14 EDT 2008


Alex Snast wrote:

> I'm new to python and i can't figure out how to write a reverse for
> loop in python
> 
> e.g. the python equivalent to the c++ loop
> 
> for (i = 10; i >= 0; --i)

use range with a negative step:

     for i in range(10-1, -1, -1):
         ...

or just reverse the range:

     for i in reversed(range(10)):
         ...

(the latter is mentioned in the tutorial, and is the second hit if you 
google for "python reverse for loop")

</F>




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