[Tutor] Code for checking whether an input string is a palindrome or not.

[Kent Johnson]

Asrarahmed Kadri wrote:
> 
> Hi,
>  
> Here is a code that reports whether the string is a palindrome or not. I 
> have posted it to help people new to programming ( i am also a newbie) 
> to understand the logic and comment on it.
>  
> Share and expand your knowledge as well as understanding...
>  
> Happy scripting....
>  
> Regards,
> Asrar
>  

Others have pointed out that there are easier ways to do this. I'll 
comment on your code.

> Code:
>  
> 
>   
> string1 = raw_input("enter a string\n")
> 
> str_len = len(string1)
> 
>  
> 
> flag = 0
> j = str_len-1
> 
> for i in range(0,(str_len-1)/2):

I think there is an off-by-one error here; try 'abcdba' as a test.

>  if string1[i] == string1[j]:

Negative indices would work well here, you don't need j at all:
   if string1[i] == string1[-i]:

This would also be a good place to use for: / else: but that is a bit 
more advanced.

Kent

>   j = j-1
> 
>  else:
>   flag = 1
>   break
> if flag ==0:
>      print "The entered string is a PALINDROME"
> else:
>      print "The entered string is not a PALINDROME"
> 
> 
> -- 
> To HIM you shall return.
> 
> 
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