Suppose a file is encrypted using the scheme in Programming Exercise 17.14. Write a program to decode an encrypted file. Your program should prompt the user to enter an input file name for the encrypted file and an output file name for the unencrypted version of the input file.

Encode the file by adding 5 to every byte in the file. Write a program that prompts the user to enter an input file name and an output file name and saves the encrypted version of the input file to the output file.