[Tutor] detecing palindromic strings

Christopher Spears cspears2002 at yahoo.com
Sat Sep 29 01:59:26 CEST 2007


I'm trying to write a script that detects if a string
is palindromic (same backward as it is forward).  This
is what I have so far:

#!/usr/bin/env python

my_str = raw_input("Enter a string: ")
    
string_list = []

for s in my_str:
    string_list.append(s)

string_list_orig = string_list

string_list.reverse()

print string_list_orig
print string_list

The problem is that the script gives results like so:
io at io-station-1 ./chap6 117> python palindromic.py
Enter a string: abc
['c', 'b', 'a']
['c', 'b', 'a']

Now I understand pointers and Python!  :-)  Since
string_list_orig is pointing to string_list, when I
reversed string_list, string_list_orig was reversed as
well.

How do I get around this?  Is there a better way to
write this script?  I can't figure out how to loop
through a string starting from the last character.


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-British military motto

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-Buster Keaton


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