import os

def isPalindrome(string):
    "Check if a string is a palindrome"
    # Get length of string
    stringLength = len(string)

    # Variable holding the new reversed string
    newString = ""

    # Position of first letter is considered 0 in string
    # Set i to position of last letter in string
    i = stringLength - 1

    # Iterate the string backwards (count backwards from length of string down to zero)
    while i >= 0:
        # Add character of position i to new reversed string
        newString = newString + string[i]
        # Decrease counter by 1
        i -= 1

    # Compare new reversed string with original string, and return result
    # Make all letters lower case to enable a correct comparison
    return string.lower() == newString.lower()

# Clear screen
os.system("clear") # Mac or Linux
#os.system("cls") # Windows

userInput = input("Input a string: ")

# Call isPalindrome function and print output based of result
if isPalindrome(userInput):
    print(userInput, "is a palindrome.")
else:
    print(userInput, "is not a palindrome.")