You have to implement encryption and decryption with Simplified DES, as discussed in the class and in Stallings 3rd edition. The permutations IP, P10, P8, and SW, and the functions fk, F, and the S-box S0 are all as described, and can be hardwired into your program. For parts (a) and (b), you will use the original S1 box as described in Stallings 3rd edition. However, for part (c), you have to use a modified S-box S1. In the modified S1, the rows 0 and 2 are the same as described for the original S1, but the rows 1 and 3 have been switched. So row 1 is 2, 1, 0, 3 and row 3 is 2, 0, 1, 3. Your program should: take as input a 8-bit block of plaintext and a 10-bit key. Show the following output (please only print what is being asked for, and nothing else): (a) the intermediate result after the SW operation while encypting. (b) the ciphertext. (c) the intermediate result after the SW operation while decrypting. (d) the result of the decryption process