Question 1

Which of the following is not a regular expression?

Accepted Answer

A) [(a+b)*-(aa+bb)]* 
B) [(0+1)-(0b+a1)*(a+b)]* 
C) (01+11+10)* 
D) (1+2+0)*(1+2)* 
A) [(a+b)*-(aa+bb)]* 
B) [(0+1)-(0b+a1)*(a+b)]* 
C) (01+11+10)* 
D) (1+2+0)*(1+2)*

Question 2

A Hamiltonian cycle in a Hamiltonian graph of order 24 has

Accepted Answer

A) 12 edges. 
B) 24 edges 
C) 23 edges 
D) None of above. 
A) 12 edges. 
B) 24 edges 
C) 23 edges 
D) None of above.

Question 3

The language accepted by a Push down Automata:

Accepted Answer

A) Type0 
B) Type1 
C) Type2 
D) Type3 
A) Type0 
B) Type1 
C) Type2 
D) Type3

Question 4

If G is "S ? a S/a", then L(G) = ?

Accepted Answer

A) a* 
B) ^ 
C) {a}+ 
D) Both (a) & (c) 
A) a* 
B) ^ 
C) {a}+ 
D) Both (a) & (c)

Question 5

The …………. is said to be ambiguous if there exist at least one word of its language that can be generated by the different production tree .

Accepted Answer

A) CFL 
B) CFG 
C) GTG 
D) None of the given 
A) CFL 
B) CFG 
C) GTG 
D) None of the given

Question 6

Which of the following problems is undecidable?

Accepted Answer

A) Membership problem for CFGs 
B) Ambiguity problem for CFGs 
C) Finiteness problem for Finite state automata FSAs 
D) Equivalence problem for FSAs 
A) Membership problem for CFGs 
B) Ambiguity problem for CFGs 
C) Finiteness problem for Finite state automata FSAs 
D) Equivalence problem for FSAs

Question 7

The regular expression 0*(10)* denotes the same set as

Accepted Answer

A) (1*0)*1* 
B) 0+(0+10)* 
C) (0+1)*10(0+1)* 
D) None of the above 
A) (1*0)*1* 
B) 0+(0+10)* 
C) (0+1)*10(0+1)* 
D) None of the above

Question 8

Which of the following strings is not generated by the following grammar? S ? SaSbS ?

Accepted Answer

A) aabb 
B) abab 
C) aababb 
D) aaabb 
A) aabb 
B) abab 
C) aababb 
D) aaabb

Question 9

Let P be a regular language and Q be context-free language such that Q ? P. (For example, let P be the language represented by the regular expression p*q* and Q be {pnqn n? N}). Then which of the following is ALWAYS regular?

Accepted Answer

A) P ? Q 
B) P - Q 
C) ?* - P 
D) ?* - Q 
A) P ? Q 
B) P - Q 
C) ?* - P 
D) ?* - Q

Question 10

Consider the NFA M shown below.
  Let the language accepted by M be L. Let L1 be the language accepted by the NFA M1, obtained by changing the accepting state of M to a non-accepting state and by changing the non-accepting state of M to accepting states. Which of the following statements is true?

Accepted Answer

A)  L1 = {0,1}* ? L 
B)  L1 = {0,1}* 
C)  L1 is a subset of L 
D)  L1 = L 
A)  L1 = {0,1}* ? L 
B)  L1 = {0,1}* 
C)  L1 is a subset of L 
D)  L1 = L

Question 11

Which one of the following statement is true for a regular language L over {a} whose minimal finite state automation has two states?

Accepted Answer

A) L must be either {an I n is odd} or {an I n is even} 
B) L must be {an I n is odd} 
C) L must be {an I n is even} 
D) L must be {an I n = 0} 
A) L must be either {an I n is odd} or {an I n is even} 
B) L must be {an I n is odd} 
C) L must be {an I n is even} 
D) L must be {an I n = 0}

Question 12

A language is represented by a regular expression (a)*(a + ba). Which of the following strings does not belong to the regular set represented by the above expression?

Accepted Answer

A) aaa 
B) aba 
C) abab 
D) aa 
A) aaa 
B) aba 
C) abab 
D) aa

Question 13

Which of the following regular expression identity is true?

Accepted Answer

A) r(*) = r* 
B) (r*s*)* = (r + s)* 
C) (r + s)* = r* + s* 
D) r*s* = r* + s* 
A) r(*) = r* 
B) (r*s*)* = (r + s)* 
C) (r + s)* = r* + s* 
D) r*s* = r* + s*

Question 14

The minimum state automaton equivalent to the above FSA has the following number of states

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
A) 1 
B) 2 
C) 3 
D) 4

Question 15

Consider the following CFG S ? aB S ? bA**spaceB ? b A ? a**spaceB ? bS A ? aS**spaceB ? aBB A ? bAA**spaceConsider the following derivation**spaceS ?aB**space?aaBB**space?aaBb**space?aabSb**space?aabbAb**space?aabbab**spaceThis derivation is

Accepted Answer

A) A leftmost derivation 
B) A rightmost derivation 
C) Both leftmost and rightmost derivation 
D) Neither leftmost nor rightmost derivation 
A) A leftmost derivation 
B) A rightmost derivation 
C) Both leftmost and rightmost derivation 
D) Neither leftmost nor rightmost derivation

Question 16

Which of the following are regular sets?

Accepted Answer

A) I and IV only 
B) I and III only 
C) I only 
D) IV only 
A) I and IV only 
B) I and III only 
C) I only 
D) IV only

Question 17

Automaton accepting the regular expression of any number of a ' s is:

Accepted Answer

A) a* 
B) ab* 
C) (a/b)* 
D) a*b*c 
A) a* 
B) ab* 
C) (a/b)* 
D) a*b*c

Question 18

The regular sets are closed under:

Accepted Answer

A) Union 
B) Concatenation 
C) Kleene closure 
D) All of the above 
A) Union 
B) Concatenation 
C) Kleene closure 
D) All of the above

Question 19

Given a Non-deterministic Finite Automation (NFA) with states p and r as initial and final states respectively and transition table as given below:   The minimum number of states required in Deterministic Finite Automation(DFA) equivalent to NFA is

Accepted Answer

A) 5 
B) 4 
C) 3 
D) 2 
A) 5 
B) 4 
C) 3 
D) 2

Question 20

The following grammar
G = (N, T, P, S)
N = {S, A, B}
T = {a, b, c}
P : S ? aSa
S ? aAa
A ? bB
B ? bB
B ? c is

Accepted Answer

A) is type 3 
B) is type 2 but not type 3 
C) is type 1 but not type 2 
D) is type 0 but not type 1 
A) is type 3 
B) is type 2 but not type 3 
C) is type 1 but not type 2 
D) is type 0 but not type 1

Which of the following is not a regular expression?

A Hamiltonian cycle in a Hamiltonian graph of order 24 has

The language accepted by a Push down Automata:

If G is "S ? a S/a", then L(G) = ?

The …………. is said to be ambiguous if there exist at least one word of its language that can be generated by the different production tree .

Which of the following problems is undecidable?

The regular expression 0(10) denotes the same set as

Which of the following strings is not generated by the following grammar? S ? SaSbS ?

Let P be a regular language and Q be context-free language such that Q ? P. (For example, let P be the language represented by the regular expression pq and Q be {pnqn n? N}). Then which of the following is ALWAYS regular?

Consider the NFA M shown below. Let the language accepted by M be L. Let L₁ be the language accepted by the NFA M1, obtained by changing the accepting state of M to a non-accepting state and by changing the non-accepting state of M to accepting states. Which of the following statements is true?

Which one of the following statement is true for a regular language L over {a} whose minimal finite state automation has two states?

A language is represented by a regular expression (a)*(a + ba). Which of the following strings does not belong to the regular set represented by the above expression?

Which of the following regular expression identity is true?

The minimum state automaton equivalent to the above FSA has the following number of states

Consider the following CFG S ? aB S ? bAspaceB ? b A ? aspaceB ? bS A ? aSspaceB ? aBB A ? bAAspaceConsider the following derivationspaceS ?aBspace?aaBBspace?aaBbspace?aabSbspace?aabbAbspace?aabbab**spaceThis derivation is

Which of the following are regular sets?

Automaton accepting the regular expression of any number of a ' s is:

The regular sets are closed under:

Given a Non-deterministic Finite Automation (NFA) with states p and r as initial and final states respectively and transition table as given below: The minimum number of states required in Deterministic Finite Automation(DFA) equivalent to NFA is

The following grammar G = (N, T, P, S) N = {S, A, B} T = {a, b, c} P : S ? aSa S ? aAa A ? bB B ? bB B ? c is

Formal Languages and Automata Theory: Part B

Computational Theory : Grammar, Language, and Complexity

Omputer Science and Theory of Computation

Automata and Turing Machines

Filters

Exam 1: Formal Languages and Automata Theory: Part A

Which of the following is not a regular expression?

A Hamiltonian cycle in a Hamiltonian graph of order 24 has

The language accepted by a Push down Automata:

If G is "S ? a S/a", then L(G) = ?

The …………. is said to be ambiguous if there exist at least one word of its language that can be generated by the different production tree .

Which of the following problems is undecidable?

The regular expression 0*(10)* denotes the same set as

Which of the following strings is not generated by the following grammar? S ? SaSbS ?

Let P be a regular language and Q be context-free language such that Q ? P. (For example, let P be the language represented by the regular expression p*q* and Q be {pnqn n? N}). Then which of the following is ALWAYS regular?

Consider the NFA M shown below. Let the language accepted by M be L. Let L1 be the language accepted by the NFA M1, obtained by changing the accepting state of M to a non-accepting state and by changing the non-accepting state of M to accepting states. Which of the following statements is true?

Which one of the following statement is true for a regular language L over {a} whose minimal finite state automation has two states?

A language is represented by a regular expression (a)*(a + ba). Which of the following strings does not belong to the regular set represented by the above expression?

Which of the following regular expression identity is true?

The minimum state automaton equivalent to the above FSA has the following number of states

Consider the following CFG S ? aB S ? bA**spaceB ? b A ? a**spaceB ? bS A ? aS**spaceB ? aBB A ? bAA**spaceConsider the following derivation**spaceS ?aB**space?aaBB**space?aaBb**space?aabSb**space?aabbAb**space?aabbab**spaceThis derivation is

Which of the following are regular sets?

Automaton accepting the regular expression of any number of a ' s is:

The regular sets are closed under:

Given a Non-deterministic Finite Automation (NFA) with states p and r as initial and final states respectively and transition table as given below: The minimum number of states required in Deterministic Finite Automation(DFA) equivalent to NFA is

The following grammar G = (N, T, P, S) N = {S, A, B} T = {a, b, c} P : S ? aSa S ? aAa A ? bB B ? bB B ? c is

Formal Languages and Automata Theory: Part B

Computational Theory : Grammar, Language, and Complexity

Omputer Science and Theory of Computation

Automata and Turing Machines

Filters

The regular expression 0(10) denotes the same set as

Let P be a regular language and Q be context-free language such that Q ? P. (For example, let P be the language represented by the regular expression pq and Q be {pnqn n? N}). Then which of the following is ALWAYS regular?

Consider the NFA M shown below. Let the language accepted by M be L. Let L₁ be the language accepted by the NFA M1, obtained by changing the accepting state of M to a non-accepting state and by changing the non-accepting state of M to accepting states. Which of the following statements is true?

Consider the following CFG S ? aB S ? bAspaceB ? b A ? aspaceB ? bS A ? aSspaceB ? aBB A ? bAAspaceConsider the following derivationspaceS ?aBspace?aaBBspace?aaBbspace?aabSbspace?aabbAbspace?aabbab**spaceThis derivation is