In: Computer Science
Using the English alphabet (i.e., mod 26 arithmetic) let plaintext = {p1, p2,… , pn} and corresponding ciphertext = {c1, c2,… , cn}. Suppose the encryption function is ci = pi + 12 (mod 26), what should be the decryption function. If you receive the ciphertext message YMDWNQXX, decrypt to recover the plaintext. What is the decryption function, and the recovered plaintext?