Understanding Vigenere Cipher: Exploring a Symmetric Encryption Algorithm

Exploring the Flowchart for Vigenere Cipher

Question 1
Open TMA Q1.fprg with Flowgorithm, and examine the flowchart for Vigenere Cipher, a symmetric encryption, . A pictorial representation of symmetric key encryption is shown in Figure Q1.1. Symmetric key encryption uses the same secret key to encrypt and decrypt a message: The sender uses a secret key to encrypt a plain text (the message) into cipher text (scrambled text that is intelligible).
The recipient uses the same secret key to decrypt the scrambled text to plain text.Figure. Q1.1 Symmetric Encryption
Study the flowchart, and execute it via the slow run button on Flowgorthm. Add breakpoints to allow you to observe the values of the variables at various points of the  flowchart.
(a) Explain and describe the purposes, input, output, and logic of each module in the flowchart:
(i) IntToArray
(ii) EncryptPhoneNumber
(iii) DecryptPhoneNumber
(b) Make postings to the Lecture Group Discussion Forum to discuss with fellow students to clarify your doubts and to explain your understanding. Then derive your own solution to parts (i) and (ii), and justify your solution using relevant postings which you agree or disagree. Failure to justify using your postings and others’ postings will incur a penalty.