Procedure
Implement one program that has two functions: one for encryption and one for decryption.
Encryption: 1. Read keys from user input. Prompt the user to enter a character for each key. 2. Read the plain text (“data”) from the input file. The name of the input file is one of the command line argument. 3. Implement your encryption algorithm. 4. Encrypt “data” and write to a file. (The name of the file is chosen by the programmer.)
Decryption: 1. Read keys from user input. Prompt the user to enter a character for each key. 5. Read the file that encrypted data was saved and extract the encrypted “data”. The name of the encrypted file is one of the command line argument. 2. Implement your decryption algorithm. 3. Decrypt the “data” and write to a file.