I have a palindrome: 'Mr. Owl ate my metal worm'

Below is my code giving me output as False.

def is_palindrome(value):
    lower = value.lower()
    return value == value[::-1]

print(is_palindrome(input('Enter the value: ')))

How can I improve my code, making it ignore case, spaces, and special characters, to identify the above palindrome and give the output as True?

CodePudding user response：

You're only making this function case insensitive, but it seems you want to ignore spaces and punctuation too.

You can do this with the string module, like so:

#!/usr/bin/env python3

x = "Mr. Owl ate my metal worm"
y = "Some other string that isn't a palindrome"

def is_palindrome(value):
    value = "".join([x for x in value.lower() if x.isalnum()])
    return value == value[::-1]

print(is_palindrome(x))
print(is_palindrome(y))

result:

True
False

isalnum() only includes letters and numbers. So the full stop, spaces and any other punctuation are removed when checking the palindrome. (thanks jodag)

CodePudding user response：

I found that there are a few issues in your code.

• First, you assigned value.lower() to lower but you did not use lower.
• Second, you have to process special characters and spaces to consider only normal characters for Palindrome.

I edited your code so that it returns True, as follows:

def is_palindrome(value):
    value = ''.join(value.split())
    value = value.replace('.', '')
    value = value.lower()
    return value == value[::-1] # mrowlatemymetalworm

print(is_palindrome(input('Enter the value: ')))

CodePudding user response：

If you want to ignore . or space while checking palindrome, then try:

def is_palindrome(value):
    lower = value.lower()
    value = value.replace(" ","").replace(".", "")
    return value == value[::-1]