This was my first C project back in 2020. I now plan to actively improve it by cleaning up the code, converting it into OOP, making it receive and process messages only instead of displaying them, and adding more ciphers. Feel free to contribute your ideas. I will improve the algorithm and rewrite it in C++ instead of C. This shouldn't be a chatbot, but a backend algorithm. As long as the original code remains unchanged, since I am busy with other things, you can make use of it.