2. If L is a regular language over E, what can be said about the languages L1 = E* - and L2 = reverse(L*)? A. Li is always regular but not L2. B. L2 is always regular but not L1. C. Li and L2 are both regular. 3. What is the language generated by the grammar G: { S → aR , R → aR | baR | b }? A. (aa*b)* B. (a*b)(a*b)* C. (aa*b)(aa*b)* 4. IfL is a regular language over some alphabet E, what can be said about the language L' = (E* – L) N reverse(L)? A. L' is surely regular. B. L' is surely non-regular. C. Its type cannot be determined without additional information.

2. If L is a regular language over E, what can be said about the languages L1 = E* - and L2 = reverse(L)? A. Li is always regular but not L2. B. L2 is always regular but not L1. C. Li and L2 are both regular. 3. What is the language generated by the grammar G: { S → aR , R → aR | baR | b }? A. (aab)* B. (ab)(ab)* C. (aab)(aab)* 4. IfL is a regular language over some alphabet E, what can be said about the language L' = (E* – L) N reverse(L)? A. L' is surely regular. B. L' is surely non-regular. C. Its type cannot be determined without additional information.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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This question is about context-free grammars and parsing, and Turing machines (TM’s). Question 1) Consider the following context-free grammar G over the alphabet Σ = {a, b, c}: S → aSb | ε | acSba | abc Using any of the grammar transformation techniques we saw in this module, construct a CNFgrammar that generates the same language as the grammar G of Question 1.Make sure you include in your answer all individual steps that you followed. Please help me with this question :)
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Find a grammar that generates language L = {b"a" : m,n>0}. %3D Find a grammar that generates language L = {b"a" : m > n, n2 0}.
subject theory of computer science Consider the following grammar G = {S, A}, S = {S}, ∑ = {a, b}, P : S → aS | aA; A → bA | b; Which of the following regular expression denotes L(G)? A.a(ab)*b B.a*b* C.aa*bb D.a*ab*b
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Let L be the language over {a, b, c} accepting all strings so that: All a’s occur after the first c. All b’s occur before the first c. The last symbol of the string is a. There are exactly twice as many b's as a's. Construct a context-free grammar generating L. You do not need an inductive proof, but you should explain how your construction accounts for each rule.
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