(C++ language)

Write a program that

1. reads a string from a user

2. converts each letter of the string to upper case

3. shifts each letter of the string by 3

4. displays the shift-encrypted string.

The program reads strings until the user enters an empty string.

How does shift encryption work?

Consider the string "See you in Xerxes' zoo?"

Converting each letter to upper case produces "SEE YOU IN XERXES' ZOO "

Shifting each letter by 3 to the right gives us "VHH BRX LQ AHUAHV' CRR"