Implementation-of-Caesar-Cipher

def caesar_cipher(text, shift, direction):
    """
    Encrypts or decrypts a message using the Caesar Cipher algorithm.

    :param text: The message to encrypt or decrypt
    :param shift: The shift value to use for encryption or decryption
    :param direction: 'encrypt' or 'decrypt'
    :return: The encrypted or decrypted message
    """
    result = ""
    for char in text:
        if char.isalpha():
            ascii_offset = 65 if char.isupper() else 97
            char_code = ord(char) - ascii_offset
            if direction == 'encrypt':
                char_code = (char_code + shift) % 26
            elif direction == 'decrypt':
                char_code = (char_code - shift) % 26
            result += chr(char_code + ascii_offset)
        else:
            result += char
    return result

def main():
    while True:
        print("Caesar Cipher Program")
        print("---------------------")
        print("1. Encrypt a message")
        print("2. Decrypt a message")
        print("3. Quit")
        choice = input("Enter your choice: ")

        if choice == '1':
            message = input("Enter the message to encrypt: ")
            shift = int(input("Enter the shift value: "))
            encrypted_message = caesar_cipher(message, shift, 'encrypt')
            print(f"Encrypted message: {encrypted_message}")
        elif choice == '2':
            message = input("Enter the message to decrypt: ")
            shift = int(input("Enter the shift value: "))
            decrypted_message = caesar_cipher(message, shift, 'decrypt')
            print(f"Decrypted message: {decrypted_message}")
        elif choice == '3':
            break
        else:
            print("Invalid choice. Please try again.")

if __name__ == "__main__":
    main()