Please help to answer below. I have seen all the other similar posts on Chegg but they are not correct. PLEASE DO NOT PASTE WRONG ANSWERS HERE AGAIN, I WILL DISLIKE. THANKS ALOT.

2 Task Two: The Substitution cipher (2 marks) A substitution cipher by a keyword works as follows. If a keyword is "STRAWBERRY", we remove the repeating characters in it to get "STRAWBEY". Then, we append the rest of the alphabet characters in reverse order (from ' Z ' to ' A ') to the keyword to construct a key i.e., "STRAWBEYZXVUQPONMLKJIHGFDC" to form a complete substitution key. Finally, we encrypt amessage by substituting its characters with the characters in the key as follows: Your task is to implement the substitution cipher. In particular, your program should - be a command-line program; - take a keyword, which is typed through command-line interface, as input; 2 - take a plaintext (message) file as input; - output a ciphertext as a file; - take a ciphertext file as input; - output a plaintext as a file; - handle any possible errors; - Write in C/C++ or Java (or else, you need to consult Mr Sionggo); - be submitted with a clear readme.txt file. NB: Ignore case. That is, you can choose whether you will input and output uppercase or lowercase characters. Also, keep (do not encrypt) special character such as full stops and commas