Python 2.5.1.7 LAB: Palindromes

Python: Check If a String is a Palindrome

Palindrome

Objectives

• improving the student's skills in operating with strings;
• encouraging the student to look for non-obvious solutions.

Scenario

Do you know what a palindrome is?
It's a word which look the same when read forward and backward. For example, "kayak" is a palindrome, while "loyal" is not.
Your task is to write a program which:

• asks the user for some text;
• checks whether the entered text is a palindrome, and prints result.

Note:

• assume that an empty string isn't a palindrome;
• treat upper- and lower-case letters as equal;
• spaces are not taken into account during the check - treat them as non-existent;
• there are more than a few correct solutions - try to find more than one.

Test your code using the data we've provided.

Test data

Sample input:
Ten animals I slam in a net

Sample output:
It's a palindrome

Sample input:
Eleven animals I slam in a net

Sample output:
It's not a palindrome

Solution Code:

""" method 1 - detailed variables"""

text = input("Enter a text\n")

a_string = text.lower().replace(' ', '')

b_string = a_string[::-1]                    

while not text:

    print("It's not a palindrome")

    break

else:

    if a_string == b_string:

        print("It's a palindrome")

    else:

        print("It's not a palindrome")

"""  method 2 - reversed() function"""

text = input("Enter a text\n")

text = text.lower().replace(" ", "")

rev_text = "".join(reversed(text))

while not text:

    print("It's not a palindrome")

    break

else:

    if text.casefold() == rev_text.casefold():

        print("It's a palindrome")

    else:

        print("It's not a palindrome")

""" methos 3 - for loop """

text = input("Enter a text\n")

def palindrome(string):

    if text == "":

        print("It's Not a palindrome")

   

    string = string.lower().replace(' ', '')

    reversed = ''

    for i in range(len(string[::-1])):

        reversed += string[::-1]

        if string == reversed:

            return "It's a palindrome"

        else:

            return "It's Not a palindrome"

print(palindrome(text))

methos 4 - while loop"""

text = input("Enter a text\n")

def palindrome(string):

    while len(string.strip()) ==0:

        return "It's Not a palindrome"

    string = string.lower().replace(' ', '')

    first, last = 0, len(string) - 1

    while(first < last):

        if(string[first] == string[last]):

            first += 1

            last -= 1

        else:

            return "It's Not a palindrome"

       

        return "It's a palindrome"

print(palindrome(text))

Still, there are other solutions, and other ways to make the mentioned solutions better. Can you think about them?

See you in the comments 👀

Remember "Learn Less, Practice More"