Problem 1.2: Encryption Extensions (100pts)

There are two subclasses that extend the encryption methods:

• Multiple Encryption: The constructor takes an integer n, and the encrypt method applies the chosen encryption method n times on the input string.
• Split Encryption: The constructor takes a number x and the encrypt method, then extracts characters from positions that are multiples of x (excluding 0), concatenates them, and appends them to the original string before applying the encryption.

Both subclasses of the encryption extensions have a decorator method that takes a encrypt function and a string, applies the function to the string in the above manner, and returns the result.

class extensions:
    """The base class for encryption extensions."""

    def decorator(self, function, message):
        """Apply the function to the message."""
        pass


class multipleencryption(extensions):
    """A class for multiple encryption extension.
    >>> cipher = shiftcipher(3)
    >>> extension = multipleencryption(2)
    >>> extension.decorator(cipher.encrypt, 'hello')
    'nkrru'
    >>> extension.decorator(cipher.encrypt, 'world')
    'cuxrj'
    """

    def __init__(self, counts=1):
        """Initialize the multiple encryption extension with a number of times."""
        "*** YOUR CODE HERE ***"

    def decorator(self, function, message):
        """Apply the function to the message multiple times."""
        "*** YOUR CODE HERE ***"


class splitencryption(extensions):
    """A class for split encryption extension.
    It extracts characters from positions that are multiples of `x` (excluding 0), 
    concatenates them, and appends them to the original string before applying the encryption method.
    >>> cipher = shiftcipher(3)
    >>> extension = splitencryption(2)
    >>> extension.decorator(cipher.encrypt, 'hello')
    'khoor'
    >>> extension.decorator(cipher.encrypt, 'world')
    'zroug'
    """

    def __init__(self, x):
        """Initialize the split encryption extension with a number x."""
        "*** YOUR CODE HERE ***"

    def decorator(self, function, message):
        """Apply the function to the message after splitting the message."""
        "*** YOUR CODE HERE ***"

Now we can finally finish the encryption system by implementing the classes above. Congratulations!

class encryption:
    """A class for encryption.
    >>> cipher = shiftcipher(3)
    >>> extension = multipleencryption(2)
    >>> encrypt = encryption(cipher, extension)
    >>> encrypt.encrypt('hello')
    'nkrru'
    >>> encrypt.encrypt('world')
    'cuxrj'
    """

    def __init__(self, method, extension):
        """Initialize the encryption with a method and an extension."""
        "*** YOUR CODE HERE ***"

    def encrypt(self, message):
        """Encrypt the message using the method and extension."""
        "*** YOUR CODE HERE ***"