Checking a Number for Palindromic Behavior

Andrew Henshaw andrew.henshaw at gtri.gatech.edu
Mon Oct 19 22:42:59 CEST 2009


><rurpy at yahoo.com> wrote in message 
>news:63dea9e7-97af-4b20-aa0a-c762d99448ab at a21g2000yqc.googlegroups.com...
>On Oct 18, 4:20 pm, MRAB <pyt... at mrabarnett.plus.com> wrote:
>> Benjamin Middaugh wrote:
>> > Thanks to everyone who helped with my query on reversing integers. I
>> > have one more simple problem I'm having trouble solving. I want to 
>> > check
>> > a number for palindromic behavior (reading the same backwards and
>> > forwards). So if I have an integer 1457 it can tell me this is not the
>> > same from both ends but 1551 is. I think the simplest way would be to
>> > work inwards from both ends checking digits for equality, but I don't
>> > know enough (yet) to do this.
>>
>> > All help is much appreciated.
>>
>> It's a palindrome if it's the same as its reverse. You already know how
>> to reverse it, and you should already know how to check whether two
>> things are the same, so... :-)
>
>Something like:
>
>def is_palidrome (n):
>    return str(n) == ''.join (reversed (str(n)))
>
>which will return True if integer n is a palidromic or False
>otherwise.

I wouldn't normally provide a direct solution to this type of request; but 
since you have, may I suggest:

def is_palindrome (n):
    return str(n) == str(n)[::-1]






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