Using rsi, rax, rdi, rdx registers, create an assembly program. The purpose of this program will be to provide simple encryption and decryption. All user input should be lower case $($no uppercase or other characters will be provided $-$ except for the last level.$)$

Grade $60$: Prompt the user for a string $($Max size $64$ char$)$ and accept their input from the keyboard; then print out a response statement and the information the user provided.

Grade $70$: Complete the previous work and then provide a simple shift cypher with an offset of your choice $($positive or negative$).$ For example $($a$=$d$,$ b$=$e$,$ c$=$f$,$ d$=$g $...$ x$=$a$,$ y$=$b$,$ z$=$c$).$

Grade $80$: Complete the previous work but also prompt the user to identify if they would like to encrypt or decrypt a message. Allow encryption to run as before but if the user indicated a decryption covert the input $($cypher text$)$ back to clear text.

Grade $90$: Keep the structure of your previous code and add a menu to allow for either a shift cypher or substitution cypher to be used; based on the user's choice. A substitution cypher is a one$-$to$-$one replacement of any character within the set. Create a data structure that has a lookup value, instead of an offset, for each character to create a substitution cypher.

Grade $100$: Complete the previous work and add uppercase letters to the encryption. Also provide for the substitution cypher read from a data file named "codebook.txt$"$ instead of being hard coded in the program.