Palindrome Checker

Question

Objective
In this programming assignment, you will create a Python script that checks whether a given word or phrase is a palindrome. A palindrome is a word, phrase, or sequence of characters that reads the same forwards and backwards (ignoring spaces, punctuation, and capitalization).
Instructions

 	Write a function called is_palindrome(input_string) that takes a single argument, input_string, which is a string containing a word or phrase.
 	The function should ignore spaces, punctuation, and capitalization when determining if the input string is a palindrome. For example, the function should return True for the input strings "A man, a plan, a canal, Panama!" and "amanaplanacanalpanama".
 	To accomplish this, you may use string manipulation techniques and/or Python's built-in string methods to filter out non-alphanumeric characters and convert the input string to lowercase.
 	Implement a palindrome-checking algorithm to determine whether the cleaned input string is a palindrome. You may use any approach you like (e.g., comparing characters, slicing, or reversing the string).
 	Write a test function called test_is_palindrome() that tests your is_palindrome() function using a few example input strings. Include test cases with palindromes, non-palindromes, and edge cases (e.g., empty strings or strings with only special characters).

Deliverables (in 30 minutes)

 	A Python script containing the is_palindrome(input_string) function and the test_is_palindrome() function.
 	A brief report (1-2 paragraphs) describing your approach and any challenges you encountered while completing the assignment.

Accepted Answer

import re

def is_palindrome(input_string: str) -> bool:
    # Remove all non-alphanumeric characters and convert to lowercase
    cleaned_string = re.sub(r'[^a-zA-Z0-9]', '', input_string).lower()
    
    # Check if the cleaned string is a palindrome
    return cleaned_string == cleaned_string[::-1]

# Implement the test function
def test_is_palindrome():
    assert is_palindrome("A man, a plan, a canal, Panama!") == True
    assert is_palindrome("Hello, World!") == False
    assert is_palindrome("") == True
    assert is_palindrome("!!!") == True
    assert is_palindrome("Was it a car or a cat I saw") == True
    print("All tests passed!")

# Run the test function
test_is_palindrome()

Title	Category	Subcategory	Difficulty	Status
All Vowels	Programming	String Manipulation	Easy	Unlock
Common Prefix Algorithm	Programming	String Manipulation	Medium	Unlock
Consecutive Letters	Programming	String Manipulation	Medium	Unlock
Count Number of Homogenous Substrings	Programming	String Manipulation	Medium	Unlock
Group Anagrams	Programming	String Manipulation	Medium	Unlock
Smallest String	Programming	String Manipulation	Easy	Unlock
Summing Up Strings #1	Programming	String Manipulation	Hard	Unlock
Summing Up Strings #2	Programming	String Manipulation	Hard	Unlock
Word Frequency	Programming	String Manipulation	Easy	Unlock
Words in a String	Programming	String Manipulation	Medium	Unlock

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