Bacon's Cipher

Bacon's cipher, invented by Francis Bacon, is a steganography method in which a message is concealed in the manner of presentation of text rather than its content.

Each letter has its position in the alphabet: $A$ is $0$, $B$ is $1$, $C$ is $2$, and so on. Every number can be represented in binary form. For example, $2$ is $10$ in binary. We expand the binary code to five digits by adding leading zeros; thus, $10$ becomes $00010$. This number can be used for encoding. To simplify, we use the following encoding rule:

$0$ corresponds to any uppercase letter, and $1$ corresponds to any decimal digit. Therefore, $00010$ ($C$) can be encoded as $ABC1D$ or $JUG9N$.

To decode, the process is reversed.