Automata Theory Multiple Choice Question & Answers (MCQs) set-12

1. The password to the admins account=”administrator”. The total number of states required to make a password-pass system using DFA would be __________
a) 14 states
b) 13 states
c) 12 states
d) A password pass system cannot be created using DFA

2.Let u=’1101’, v=’0001’, then uv=11010001 and vu= 00011101.Using the given information what is the identity element for the string?
a) u-1
b) v-1
c) u-1v-1
d) ε
3. Number of states require to accept string ends with 10.
a) 3
b) 2
c) 1
d) can’t be represented.
4. If δ is the transition function for a given NFA, then we define the δ’ for the DFA accepting the same language would be:
Note: S is a subset of Q and a is a symbol.
a) δ’ (S, a) =Upϵs δ (p, a)
b) δ’ (S, a) =Up≠s δ (p, a)
c) δ’ (S, a) =Upϵs δ(p)
d) δ’ (S) =Up≠s δ(p)
5. If L is a regular language, Lc and Lr both will be:
a) Accepted by NFA
b) Rejected by NFA
c) One of them will be accepted
d) Cannot be said
6. An e-NFA is ___________ in representation.
a) Quadruple
b) Quintuple
c) Triple
d) None of the mentioned
7. Reverse of (0+1)* will be
a) Phi
b) Null
c) (0+1)*
d) (0+1)
8. (0+ε) (1+ε) represents
a) {0, 1, 01, ε}
b) {0, 1, ε}
c) {0, 1, 01 ,11, 00, 10, ε}
d) {0, 1}
9. (a + b*c) most correctly represents:
a) (a +b) *c
b) (a)+((b)*.c)
c) (a + (b*)).c
d) a+ ((b*).c)
10. Is it possible to obtain more than one regular expression from a given DFA using the state elimination method?
a) Yes
b) No
11. Regular expressions are closed under
a) Union
b) Intersection
c) Kleen star
d) All of the mentioned
12. Which of the following do Regexps do not find their use in?
a) search engines
b) word processors
c) sed
d) none of the mentioned
13. The action of parsing the source code into proper syntactic classes is known as:
a) Parsing
b) Interpretation analysis
c) Lexicography
d) Lexical Analysis
14. Which among the following is the closure property of a regular language?
a) Emptiness
b) Universality
c) Membership
d) None of the mentioned
15. If L is a language, the reversal of the language can be represented as:
a) L’
b) Lc
c) Lr
d) more than one option is correct