Question 1

Which of the following statement is wrong?

Accepted Answer

A) Any regular language can be generated by a context-free grammar 
B) Some non-regular languages cannot be generated by any CFG 
C) the intersection of a CFL and regular set is a CFL 
D) All non-regular languages can be generated by CFGs. 
A) Any regular language can be generated by a context-free grammar 
B) Some non-regular languages cannot be generated by any CFG 
C) the intersection of a CFL and regular set is a CFL 
D) All non-regular languages can be generated by CFGs.

Question 2

Which one of the following languages over the alphabet {0,1} is described by the regular expression: (0+1)*0(0+1)*0(0+1)*?

Accepted Answer

A) The set of all strings containing the substring 00. 
B) The set of all strings containing at most two 0's. 
C) The set of all strings containing at least two 0's. 
D) The set of all strings that begin and end with either 0 or 1. 
A) The set of all strings containing the substring 00. 
B) The set of all strings containing at most two 0's. 
C) The set of all strings containing at least two 0's. 
D) The set of all strings that begin and end with either 0 or 1.

Question 3

A language is regular if and only if

Accepted Answer

A) Accepted by DFA 
B) Accepted by PDA 
C) Accepted by LBA 
D) Accepted by Turing machine 
A) Accepted by DFA 
B) Accepted by PDA 
C) Accepted by LBA 
D) Accepted by Turing machine

Question 4

P, Q, R are three languages. If P & R are regular and if PQ=R, then

Accepted Answer

A) Q has to be regular 
B) Q cannot be regular 
C) Q need not be regular 
D) Q has to be a CFL 
A) Q has to be regular 
B) Q cannot be regular 
C) Q need not be regular 
D) Q has to be a CFL

Question 5

The following CFG is in S ? AB**spaceB ? CD**spaceB ? AD**spaceB ? b**spaceD ? AD**spaceD ? d**spaceA ? a**spaceC ? a

Accepted Answer

A) Chomsky normal form but not strong Chomsky normal form 
B) Weak Chomsky normal form but not Chomsky normal form 
C) Strong Chomsky normal form 
D) Greibach normal form 
A) Chomsky normal form but not strong Chomsky normal form 
B) Weak Chomsky normal form but not Chomsky normal form 
C) Strong Chomsky normal form 
D) Greibach normal form

Question 6

A?abA a type __________productions

Accepted Answer

A) Type 0 
B) Type 1 
C) Type 2 
D) Type 3 
A) Type 0 
B) Type 1 
C) Type 2 
D) Type 3

Question 7

"S ?a S", what is the type of this production?

Accepted Answer

A) Type 0 
B) Type 1 
C) Type 2 
D) Type 3 
A) Type 0 
B) Type 1 
C) Type 2 
D) Type 3

Question 8

Which of the statements is true:

Accepted Answer

A) The complement of a regular language is always regular. 
B) Homomorphism of a regular language is always regular. 
C) Both of the above are true statements 
D) None of the above 
A) The complement of a regular language is always regular. 
B) Homomorphism of a regular language is always regular. 
C) Both of the above are true statements 
D) None of the above

Question 9

How many strings of length less than 4 contains the language described by the regular expression (x+y)*y(a+ab)*?

Accepted Answer

A) 7 
B) 10 
C) 12 
D) 11 
A) 7 
B) 10 
C) 12 
D) 11

Question 10

A minimum state deterministic finite automation accepting the language L={W W ? {0,1}*, number of 0s and 1s in are divisible by 3 and 5, respectively} has

Accepted Answer

A) 15 states 
B) 11 states 
C) 10 states 
D) 9 states 
A) 15 states 
B) 11 states 
C) 10 states 
D) 9 states

Which of the following statement is wrong?

Which one of the following languages over the alphabet {0,1} is described by the regular expression: (0+1)0(0+1)0(0+1)*?

A language is regular if and only if

P, Q, R are three languages. If P & R are regular and if PQ=R, then

The following CFG is in S ? ABspaceB ? CDspaceB ? ADspaceB ? bspaceD ? ADspaceD ? dspaceA ? a**spaceC ? a

A?abA a type __________productions

"S ?a S", what is the type of this production?

Which of the statements is true:

How many strings of length less than 4 contains the language described by the regular expression (x+y)y(a+ab)?

A minimum state deterministic finite automation accepting the language L={W W ? {0,1}*, number of 0s and 1s in are divisible by 3 and 5, respectively} has

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 statement is wrong?

Which one of the following languages over the alphabet {0,1} is described by the regular expression: (0+1)*0(0+1)*0(0+1)*?

A language is regular if and only if

P, Q, R are three languages. If P & R are regular and if PQ=R, then

The following CFG is in S ? AB**spaceB ? CD**spaceB ? AD**spaceB ? b**spaceD ? AD**spaceD ? d**spaceA ? a**spaceC ? a

A?abA a type __________productions

"S ?a S", what is the type of this production?

Which of the statements is true:

How many strings of length less than 4 contains the language described by the regular expression (x+y)*y(a+ab)*?

A minimum state deterministic finite automation accepting the language L={W W ? {0,1}*, number of 0s and 1s in are divisible by 3 and 5, respectively} has

Formal Languages and Automata Theory: Part B

Computational Theory : Grammar, Language, and Complexity

Omputer Science and Theory of Computation

Automata and Turing Machines

Filters

Which one of the following languages over the alphabet {0,1} is described by the regular expression: (0+1)0(0+1)0(0+1)*?

The following CFG is in S ? ABspaceB ? CDspaceB ? ADspaceB ? bspaceD ? ADspaceD ? dspaceA ? a**spaceC ? a

How many strings of length less than 4 contains the language described by the regular expression (x+y)y(a+ab)?