Q. Regular expression for the complement of language L = {a^n b^m I n ≥ 4, m ≤ 3} is

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Q. We can show that the clique problem is NP-hard by proving that

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Q. Given the recursively enumerable language (LRE), the context sensitive language (LCS) the recursive language (LREC) the context free language (LCF) and deterministic context free language (LDCF) The relationship between these families is given by

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Q. Match the following:

       List- I                                                List -II
a. Context free grammar               i. Linear bounded automaton
b. Regular grammar                     ii. Pushdown automaton
c. Context sensitive grammar     iii. Turing machine
d. Unrestricted grammar             iv. Deterministic finite automaton

code:
a   b    c    d

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Q. According to pumping lemma for context free languages:
Let L be an infinite context free language, then there exists some positive integer m such that any w ∈ L with I w I ≥ m can be decomposed as w = u v x y z

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Q. The equivalent production rules corresponding to the production rules

S → Sα1 | Sα2 | β1 | β2 

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Q. If all the production rules have single non - terminal symbol on the left side, the grammar defined is :

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Q. Minimal deterministic finite automaton for the language L = {0n | n ≥ 0 , n ≠ 4} will have

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Q. The regular expression corresponding to the language L where L = { x ∈{0, 1}* | x ends with 1 and does not contain substring 00 } is :

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Q. A context free grammar for L = { w | n0 (w) > n1 (w)} is given by :

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Q. Given the following two statements :

S1: If L1 and L2 are recursively enumerable languages over Σ, then L1 ⋃ L2 and L1 ⌒ L2 are also recursively enumerable.

S2: The set of recursively enumerable languages is countable.

Which of the following is correct?

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Q. Given the following grammars :

G1: S → AB|aaB

A → aA | ∈

B → bB | ∈

G2: S → A | B

A → a A b | ab

B → a b B | ∈

Which of the following is correct?

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Q. Let L be any language. Define even (W)  as the  strings  obtained by extracting from W the letters in the even-numbered positions and even (L) = {even (W) | W ԑ L}. We define another language Chop (L) by removing the two leftmost symbols of every string in L given by Chop(L) = {W | v W ԑ L,with | v | = 2}.

If L is regular language then

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Q. Given the following two grammars :

G1 :     S → AB | aaB

A → a | Aa

B → b

G2: S→ aSbS|bSaS|λ

Which statement is correct ?

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Q. Match the following:

List-I                                                            List-II

a. Chomsky Normal form                       i.  S→ bSS|aS|c

b. Greibach Normal form                        ii.  S→ aSb|ab

c. S-grammar                                           iii. S→ AS|a

                                                                         A→ SA|b

d. |LL grammar                                        iv. S→ aBSB

                                                                         B→ b

Codes:
a       b       c       d

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Q. Given the following two languages :

L1 = {anbn |n≥1} ∪ {a}

L2= {w C wR|we {a,b}*}

Which statement is correct ?

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Q. The solution of the recurrence relation of T(n) = 3T ( floor (n/4) ) +  n is

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Q. The number of strings of length 4 that are generated by the regular expression (0|?) 1+2* (3|?), where | is an alternation character, {+, *} are quantification characters, and ? is the null string, is:

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Q. Which of the following is FALSE ?

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Q. Consider the languages L1 = ϕ, and L2 = {1}. Which one of the following represents
L1* U L2* L1* ?

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