Why this Palindrome Recursive Function giving me True in all cases?

Question

I have tried to write a recursive version of the Palindrome function. But it is giving me True in all the cases. why?

def isPalindrome(inputString):
   if len(inputString)==0 or 1:
      return True
   elif inputString[0]==inputString[-1]:
      return isPalindrome(inputString[1:-1])
   else:
      return False

Why False is not working for non Palindrome Text.

`if len(inputString)==0 or 1:` is not the right way to test multiple values. See https://stackoverflow.com/q/15112125/494134 — John Gordon, Jul 24 '21 at 18:37

score 1 · Answer 1 · answered Jul 24 '21 at 18:39

1

Short circuit evaluation.

def is_palindrome(input_string):
    if len(input_string) == 0 or len(input_string) == 1:
        return True
    elif input_string[0] == input_string[-1]:
        return is_palindrome(input_string[1:-1])
    else:
        return False


print(is_palindrome('your_string')) # False

answered Jul 24 '21 at 18:39

Ibrahim Berber

842
2
16

Thanks a lot. The above code is working. But where I was wrong in the above code? – Pushpendra Jul 24 '21 at 18:44
1

That was quick! I got it where I was making mistake. – Pushpendra Jul 24 '21 at 18:47

Why this Palindrome Recursive Function giving me True in all cases?

1 Answers1