# Write a simple encryption/decryption program

Cryptography, or cryptology is the practice and study of techniques for secure communication in the presence of third parties called adversaries. Until modern times, cryptography referred almost exclusively to encryption, which is the process of converting ordinary information (called plaintext) into unintelligible form (called ciphertext). Decryption is the reverse, in other words, moving from the unintelligible ciphertext back to plaintext. A cipher (or cypher) is a pair of algorithms that carry out the encryption and the reversing decryption. For this assignment you will write a simple encryption/decryption program called GMUCipher. A GMUCipher uses a document as the cipher key, and the cipher itself uses numbers that reference the words within the text. For example, we can use an edition of The Declaration of Independence as the cipher key. The cipher you will write will use a pair of numbers corresponding to each letter in the text. The first number denotes the position of a word in the key text (starting at 0), and the second number denotes the position of the letter in the word (also starting at 0). For instance, given the following key text (the numbers correspond to the index of the first word in the line): [0] ‘Twas brillig, and the slithy toves Did gyre and gimble in the wabe; [13] All mimsy were the borogoves, And the mome raths outgrabe. [23] “Beware the Jabberwock, my son! The jaws that bite, the claws that catch! [36] Beware the Jubjub bird, and shun The frumious Bandersnatch!” [45] He took his vorpal sword in hand: Long time the manxome foe he sought—” The word “computer” can be encoded with the following pairs of numbers: 35,0 catch 5,1 toves 43,3 frumious 48,3 vorpal 22,1 outgrabe. 34,3 that 23,6 “Beware 7,2 gyre Placing these pairs into a cipher text, we get the following: 35,0,5,1,43,3,48,3,22,1,34,3,23,6,7,2 If you are encoding a phrase, rather than just a single word, spaces in the original English phrase will also appear in the ciphered text. So, the phrase “all done” (using the above Jabberwocky poem) might appear as: 0,3,1,4,13,1 6,0,46,2,44,2,3,2 Only spaces in the key text should be considered delimiters. All other punctuation in the key text is to be considered part of a key word. Thus, the first word in the Jabberwocky poem, ‘Twas, will have the following characters and positions for key word 0: Position 0: ‘ Position 1: T Position 2: w Position 3: a Position 4: s Please read the Description for all details, and check the Rubric for all requirements.

Pages (550 words)
Approximate price: -

Why Choose Us

Quality Papers

We value our clients. For this reason, we ensure that each paper is written carefully as per the instructions provided by the client. Our editing team also checks all the papers to ensure that they have been completed as per the expectations.

Over the years, our Acme Homework has managed to secure the most qualified, reliable and experienced team of writers. The company has also ensured continued training and development of the team members to ensure that it keep up with the rising Academic Trends.

Affordable Prices

Our prices are fairly priced in such a way that ensures affordability. Additionally, you can get a free price quotation by clicking on the "Place Order" button.

On-Time delivery

We pay strict attention on deadlines. For this reason, we ensure that all papers are submitted earlier, even before the deadline indicated by the customer. For this reason, the client can go through the work and review everything.

100% Originality

At Graduate Assistants, all papers are plagiarism-free as they are written from scratch. We have taken strict measures to ensure that there is no similarity on all papers and that citations are included as per the standards set.

Our support team is readily available to provide any guidance/help on our platform at any time of the day/night. Feel free to contact us via the Chat window or support email: support@acmehomework.com.

Try it now!

## Calculate the price of your order

We'll send you the first draft for approval by at
Total price:
\$0.00

How it works?

Fill in the order form and provide all details of your assignment.

Proceed with the payment

Choose the payment system that suits you most.

Our Services

Graduate Assistants has stood as the world’s leading custom essay writing services providers. Once you enter all the details in the order form under the place order button, the rest is up to us.

## Essay Writing Services

At Graduate Assistants, we prioritize on all aspects that bring about a good grade such as impeccable grammar, proper structure, zero-plagiarism and conformance to guidelines. Our experienced team of writers will help you completed your essays and other assignments.