Part D - Programming in C = Below is 2 x 2 encoding and decoding matrix. The below output is assumed A = 0, B = 1, C = 2,D = 3, ... space 4, 26. So, the total alphabet n is 27. Figure QD1 - QD4 show the possible output Welcome. Please choose your option: 1. Finds inverse key. 2. Encoding 3. Decoding FIGURE QD1: Main Interface If user choose Option 1: Find inverse key:- Please enter the key value, k (26 10 15 10 (1,5 ) User key in The inverse key is 22 6 13 6 33) FIGURE QD2: Find the inverse If user choose Option 2: Encoding process:- Please enter the key value, k (26 10 15 10) User key in Please enter the plaintext, p ATOA You can use number to represent the space. The output is (13 ) Computer generate the output and the ciphertext c. The ciphertext, c is CNDL FIGURE QD3: Encoding process If user choose Option 3: Decoding process:- Please enter the key value, k 26 |(3510) User key in Please enter the plaintext, p CNDL You can use number to represent the space. | The output is (26 19 Computer generate the output and the plaintext p. The plaintext, p is ATOA FIGURE QD4: Decoding process Using C, write a program of 2 x 2 calculate inverse key, encoding and decoding matrix. Use the following information for the program: Your system will assume A = 11, B = 12, C = 13, D = 14, ... Space A= 10. So, the total alphabet n is 27. = =