Write a C++ program and then convert it into and an ARMv8 program that performs primitive encryption and decryption of ASCII text (sometimes known as the Caesar Cipher) by shifting the letters according to the English alphabet by the given number of places. The program inputs the string to encrypt or decrypt, the operation to perform (encryption or decryption), and the number of places to shift (between 1 and 25). If the end of the alphabet is reached, shifting continues from the beginning, i.e. after z comes a. As an example of encryption, the letter y shifted by three places becomes b, the letter H becomes K, and the string Hello World becomes Khoor Zruog. The case of the letters should not change (lowercase remains lowercase, and uppercase remains uppercase). Also, any non-letter character, such as digit or symbol, should remain unchanged.