(Solved Homework): Programming languages are often described using an extended form of context-free grammar, where square brackets

Programming languages are often described using an extended form of context-free grammar, where square brackets are used to denote an optional construct. For example, A → B[C]D says that an A can be replaced by a B and a D, with an optional C between them. This notation does not allow us to describe anything but context-free languages, since an extended production can always be replaced by several conventional productions.

Suppose a grammar has the extended productions:

A → B[CD]EF | BC[DE]F

Convert this pair of extended productions to conventional productions. Identify, from the list below, the conventional productions that are equivalent to the extended productions above.

a) A → BCDEF | BEF

b) A → BA₁F

A₁ → CD | DE | ε

c) A → BA₁EF | BCA₂F

A₁ → CD | ε

A₂ → DE | ε

d) A → BA₁EF | BCA₂F

A₁ → CD

A₂ → DE

What is the answer? Explain me Plz

Expert Answer

Given grammar :-

A → B[CD]EF | BC[DE]F

says that an A can be replaced by a B and a EF, with an optional CD between them or A can be replaced by a BC and a F, with an optional DE between them.

Conventional productions that is equivalent to the productions above :-

c) A → BA1EF | BCA2F

A1 → CD | ε

A2 → DE | ε

Hint :-

a is not possible because A → BCDEF is not always a production

b is not possible because A → BA1EF | BCA2F; A1 → CD | ε; A2 → DE | ε; does not give B[CD]EF | BC[DE]F

d is also not possible because it does not have ε

only option c gives A → B[CD]EF | BC[DE]F

Top Quality and Well-Researched Papers

All ourbpapers are written from scratch. In fact, Clients who ask for paraphrasing services are highly discouraged. We have writers ready to craft any paper from scratch and deliver quality ahead of time.

Professional and Experienced Academic Writers

Our writers keeps you posted on your papers progress - providing you with paper outline/draft. You are also at liberty to communicate directly with your writer.

Free Unlimited Revisions

If you think we missed something, send your order for a free revision. You have 10 days to submit the order for review after you have received the final document. You can do this yourself after logging into your personal account or by contacting our support.

Prompt Delivery and 100% Money-Back-Guarantee

All papers are always delivered on time, in many cases quite ahead of time. In case we need more time to master your paper, we may contact you regarding the deadline extension. In case you cannot provide us with more time, a 100% refund is guaranteed.

Original & Confidential

We use several writing tools checks to ensure that all documents you receive are free from plagiarism. Our editors carefully review all quotations in the text. We also promise maximum confidentiality in all of our services.

24/7 Customer Support

Our support agents are available 24 hours a day 7 days a week and committed to providing you with the best customer experience. Get in touch whenever you need any assistance.

Try it now!

Calculate the price of your order

Type of paper needed:

Pages:

Academic level:

Total price:

$0.00

How it works?

Follow these simple steps to get your paper done

Place your order

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

Proceed with the payment

Choose the payment system that suits you most.

Receive the final file

Once your paper is ready, we will email it to you.

Our Services

No need to work on your paper at night. Sleep tight, we will cover your back. We offer all kinds of writing services.

Essays

Essay Writing Service

No matter what kind of academic paper you need and how urgent you need it, you are welcome to choose your academic level and the type of your paper at an affordable price. We take care of all your paper needs and give a 24/7 customer care support system.

Admissions

Admission Essays & Business Writing Help

An admission essay is an essay or other written statement by a candidate, often a potential student enrolling in a college, university, or graduate school. You can be rest assurred that through our service we will write the best admission essay for you.

Reviews

Editing Support

Our academic writers and editors make the necessary changes to your paper so that it is polished. We also format your document by correctly quoting the sources and creating reference lists in the formats APA, Harvard, MLA, Chicago / Turabian.

Reviews

Revision Support

If you think your paper could be improved, you can request a review. In this case, your paper will be checked by the writer or assigned to an editor. You can use this option as many times as you see fit. This is free because we want you to be completely satisfied with the service offered.