--- John Fouhy <[EMAIL PROTECTED]> wrote:
> On 29/03/06, Hoffmann <[EMAIL PROTECTED]> wrote:
> > Hi John,
> >
> > (1) vehicle[index] is: 'c'
> > (2) If index = index = 1, so vehicle[index]
> becomes:
> > 'a'
>
> What I'm getting at here is that, by changing index,
> we can change
> which letter we are looking at. And index is a
> number, which means
> it's easier to reason about than letters are.
>
> Let's have a look at a possible solution:
>
> >>> vehicle = 'car'
> >>> index = 2
> >>> print vehicle[index]
> r
> >>> index = 1
> >>> print vehicle[index]
> a
> >>> index = 0
> >>> print vehicle[index]
> c
>
> Notice that the three print statements are
> identical. That suggests
> we could write the code in a loop, with 'print
> vehicle[index]' in the
> body of the loop. Can you have a go at that?
>
> --
> John.
> _______________________________________________
Hi John,
We are almost there. I changed the code and, at least,
I got the correct output. However, I also got a
traceback. I didn't understand the traceback. Could
you clarify that?
Thanks,
Hoffmann
ps: The new code:
>>> vehicle='car'
>>> index = -1 #index of the last letter
>>> lenght = len(vehicle)
>>> last = vehicle[lenght-1]
>>>
>>> while last >= vehicle[0]:
letter=vehicle[index]
print letter
index -= 1
r
a
c
Traceback (most recent call last):
File "<pyshell#40>", line 2, in -toplevel-
letter=vehicle[index]
IndexError: string index out of range
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
_______________________________________________
Tutor maillist - Tutor@python.org
http://mail.python.org/mailman/listinfo/tutor
