Caesar_Cipher_En.py

#Take a string and an interger shift value 
#Return Encode string 

def caesar_cipher(text, shift): 
    encrypted = []# create a list to hold the encrypted characters as they are processed

    for char in text: #Iterate over each character of the input string 
        if char.isalpha():#Check if character is an alphabetic letter, ignoring number and punctuation etc
            shift_amount = shift % 26 #Normalise the shift to a value between 0 and 25 
            new_ord = ord(char) + shift_amount #ord is a function used to convert character to Unicode int 

            if char.islower():#Check if the char is lowercase 
                if new_ord > ord("z"):#Ensuring that if the new Unicode+shift exceed z 
                    new_ord -=26 # -26 is wrap around the alphabet 
            else: #handle uppercase senario
                if new_ord > ord("Z"): 
                    new_ord -=26 

            encrypted.append(chr(new_ord)) #chr() is a converter from unicode to character and append it into the list 
        else: #If the character is not alphabetic then put it back to the list unchanged 
            encrypted.append(char)

    return "".join(encrypted) #Convert the list of character back into a single string and returns it 

text = input("Enter a string: ")
shift = int(input("Enter number of shift: "))

encoded_text = caesar_cipher(text, shift)
print(f"The encoded text is {encoded_text}")