Description

This PR implements the Diffie-Hellman Key Exchange and MonoAlphabetic Cipher algorithms.

Key Changes:

1. Diffie-Hellman Key Exchange:

   • Added DiffieHellman.java under the ciphers directory.
   • The implementation allows two users (Person A and Person B) to securely generate a shared secret key over an insecure channel using large prime numbers and modular arithmetic.
   • The code prompts the users to input their secret numbers and performs the necessary calculations to exchange and compute the shared secret keys.

2. MonoAlphabetic Cipher:

   • Added MonoAlphabetic.java under the ciphers directory.
   • The implementation allows the user to either encrypt or decrypt data using a predefined substitution cipher, where each letter of the alphabet is replaced with a corresponding letter.
   • The user is prompted to enter the data, and the cipher is applied to return either the encrypted or decrypted result.

Both algorithms are utility classes, with private constructors to prevent instantiation and static methods to handle their respective functionalities.

• I have read CONTRIBUTING.md.
• This pull request is all my own work -- I have not plagiarized it.
• All filenames are in PascalCase.
• All functions and variable names follow Java naming conventions.
• All new algorithms have a URL in their comments that points to Wikipedia or other similar explanations.
• All new code is formatted with clang-format -i --style=file path/to/your/file.java