# Coding challenge
Alice and Bob are security concious and hence use encryption to exchange all their messages. They use multiple encryption systems.
Design a system that allows Alice and Bob to communicate using the following encryption schemes:
- [Cesar Cipher](https://en.wikipedia.org/wiki/Caesar_cipher)
- [Keyword Cipher](https://www.geeksforgeeks.org/keyword-cipher/)
- [Playfair Cipher](https://en.wikipedia.org/wiki/Playfair_cipher)
## Note:
- The implementation should be in an Object Oriented Programming language.
- The design of the system should follow OOPS fundamentals.
- It's safe to assume that the encryption keys are constant.
- Write unit tests or a CLI program to demonstrate the usage of your system.
- Switching between Encryption schemes should be configurable.