[Tutor] Soem list operation questions?

[Guillermo Fernandez Castellanos]

hi!

> 1. Is there any easy way to compeltely reverse a list so that the last index
> becomes the first, etc.?
The doc is your friend :-)
http://www.python.org/dev/doc/maint24/lib/typesseq-mutable.html
"""s.reverse()          reverses the items of s in place"""

>>> a=[1,2,3,4]
>>> a.reverse()
>>> a
[4, 3, 2, 1]

> 2. Is there any way to take seperate integers in a list and combine them
> into digits of one number? (e.g. changing [1,2,3,4] into 1234)
Mmm...
Well, there is a way:
lambda l: int("".join([str(x) for x in l]))

>>> a=[1,2,3,4]
>>> c=lambda l: int("".join([str(x) for x in l]))
>>> c(a)
1234

Let's have a more detailed of what I do by writting the non-ofuscated
equivalent code:

def c(l):
   # Converting all elements of the list into strings
   a=[str(x) for x in l]
   # Joigning all those strings into a single string
   s="".join(a)
   # Converting the new string into an integer
   int(s)

There's probably a better way to do it, but in the meantime you can
start using this.

Enjoy!

Guille