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Recent questions tagged regularlanguages
0
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1
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1
Practice Question
How to prove that $ (a+b)^*ab(a+b)^*+b^*a^* = (a+b)^*$
asked
5 days
ago
in
Theory of Computation
by
Hardik Maheshwari
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97
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24
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theoryofcomputation
regularexpressions
regularlanguages
regulargrammar
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0
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2
MadeEasy Test Series
$L^{*}\{{\epsilon }\}=L^{+}$. True or False? (Given L is a language)
asked
5 days
ago
in
Theory of Computation
by
CS.user
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97
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45
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regularlanguages
madeeasytestseries
theoryofcomputation
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0
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3
Made Easy Test
Which of the following RE are equivalent ? (a+b)*abb(a+b)* (a+b)*a(a+b)*bb(a+b)* (a+b)*ab(a+b)*b(a+b)*
asked
6 days
ago
in
Theory of Computation
by
Shamim Ahmed
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28
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madeeasytestseries
regularlanguages
0
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4
theory of autometa
let M be a finite autometa .let M' denote the machine obtained by interchanging the final and non final state L(M) U L(M') =sigma* L(M) $\cap$ L(M') =$\Phi$ i am sure that 1st is true but for 2nd take an example so 2nd become false but given that both are true for DFA where i am doing mistake ??
asked
Jan 11
in
Theory of Computation
by
Gurdeep Saini
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7.7k
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30
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finiteautomata
theoryofcomputation
regularlanguages
regularexpressions
0
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0
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5
Made Easy test series
L1 is regular, L2 and L3 are CFL L1 is regular, L2 is CFL and L3 is CSL L1 is CFL but not regular,L2 is CSL but not CFL,L3 is CFL L1, L2 and L3 are CFL
asked
Jan 9
in
Theory of Computation
by
Sambhrant Maurya
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1.2k
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25
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madeeasytestseries
regularlanguages
contextfreelanguage
0
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0
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6
Made Easy test series
asked
Jan 9
in
Theory of Computation
by
Sambhrant Maurya
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1.2k
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44
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madeeasytestseries
regularlanguages
regularexpressions
0
votes
0
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7
Regular Language
Which of the following option is correct regarding dependability? A. Given a regular language R and contextfree C. Is every string in R also in C, i.e., Is L(R)⊆L(C) decidable? B. Given a regular language R and contextfree C. Is every string in C also in R, i.e., Is L(C)⊆L(R) decidable? C. Both (A) and (B) D. None of these
asked
Jan 7
in
Theory of Computation
by
Shivangi Parashar 2
(
329
points)

21
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theoryofcomputation
regularlanguages
0
votes
0
answers
8
Regular Language
If L ≠ ∅ and L is regular then L is the union of regular language A1, . . . , An where each Ai is accepted by a DFA with exactly one final state .Please elaborate how this statement is true.
asked
Jan 7
in
Theory of Computation
by
Shivangi Parashar 2
(
329
points)

30
views
theoryofcomputation
regularlanguages
0
votes
1
answer
9
Regular Expression Statements
Can anyone explain how S2 is false,I did not understand their logic.
asked
Jan 1
in
Theory of Computation
by
sripo
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1.3k
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49
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regularexpressions
theoryofcomputation
finiteautomata
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expression
madeeasytestseries
0
votes
1
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10
regular language
Stare true and false Is this regular ? now if it is not regular then i want to change in the question in place of (a+b)+ if it is (a+b)* then ??
asked
Dec 31, 2018
in
Theory of Computation
by
Gurdeep Saini
Loyal
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7.7k
points)

51
views
theoryofcomputation
regularlanguages
regularexpressions
+1
vote
2
answers
11
NTA NET DEC 2018
asked
Dec 30, 2018
in
Theory of Computation
by
rakeshcoresoft
(
83
points)

85
views
regularlanguages
regularexpressions
+1
vote
1
answer
12
Closure Properties
What is difference between Σ* and L* ? Which is true ? S1 : Σ* – {ϵ} = Σ+ S2 : L* – {ϵ} = L+ .
asked
Dec 24, 2018
in
Theory of Computation
by
anurag sharma
(
103
points)

100
views
theoryofcomputation
closureproperty
regularlanguages
0
votes
0
answers
13
#TOC Regular Language Is this a regular set?
WXW^R where W,X belongs to (0,1)* W^R is reverse of a string!
asked
Dec 22, 2018
in
Theory of Computation
by
iarnav
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9.4k
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47
views
theoryofcomputation
regularlanguages
finiteautomata
regularexpressions
0
votes
0
answers
14
UGC NET Doubt
https://gateoverflow.in/13365/ugcnetdec2014iii24 i’ve a small doubt in the solution of this question how is (a+b)*ba(a+b)* complement of the given language?
asked
Dec 14, 2018
in
Theory of Computation
by
aditi19
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2.2k
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55
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ugc
regularlanguages
regulargrammar
0
votes
1
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15
UGC NET 2016
Let L be the language generated by regular expression 0*10* and accepted by the deterministic finite automata M. Consider the relation RM defined by M. As all states are reachable from the start state, RM has _____ equivalence classes. pls give a detailed solution
asked
Dec 14, 2018
in
Theory of Computation
by
aditi19
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2.2k
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55
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#dfa
finiteautomata
equivalenceclasses
regularlanguages
regularexpressions
+1
vote
1
answer
16
TOC Which is(are) regular? Please explain 1 and 4.
Which of the following languages is regular? L = { bba (ba)* a^n1  n> 0 } L = {a^nb^n  n < 1000 } L = {a^nb^k  n is odd or k is even } L = {wxw^R  w,x ∈(0+1)* } 1, 3 and 4 2, 3, 4 2, 3 1, 2, 3, 4
asked
Dec 13, 2018
in
Theory of Computation
by
rahuljai
(
437
points)

90
views
contextsensitive
regularlanguages
contextfreelanguage
theoryofcomputation
regularexpressions
+2
votes
1
answer
17
Regular language
L={a^m b^n  mn=even} Is this language a regular language?
asked
Dec 12, 2018
in
Theory of Computation
by
AIkiran01
(
209
points)

176
views
theoryofcomputation
finiteautomata
regularlanguages
regularexpressions
identifyclasslanguage
0
votes
0
answers
18
THEORY OF COMPUTATION
Let $L_1= (0+1)^* , L_2=(01^*0 +1^*) \text{ and } L3=(01^+0 +1^+ + \epsilon) $. If $L=L_1 \cap L_2 \cap L_3$ Then find the number of strings in $L$ which do not contain $11$.
asked
Dec 10, 2018
in
Theory of Computation
by
ROHIT SHARMA 5
(
143
points)

41
views
theoryofcomputation
regularlanguages
0
votes
0
answers
19
proving a language is regular based on two regular language over same $\Sigma$ (complicated)
asked
Dec 9, 2018
in
Theory of Computation
by
csenoob
(
21
points)

28
views
regularlanguages
theoryofcomputation
finiteautomata
closureproperty
0
votes
0
answers
20
going from equivalnce classes into a DFA
Hello all, I saw an interesting question and i was wondering how to solve it. basically the subject i am having trouble with is going from equivalence classes of $R_L$ to building a DFA. The question: L is a language over {0,1}, for which ... how do you go from equivalence classes to finding the DFA? don't understand it. thank you very much for your help
asked
Dec 5, 2018
in
Theory of Computation
by
csenoob
(
21
points)

81
views
#dfa
finiteautomata
theoryofcomputation
compilerdesign
regularlanguages
0
votes
0
answers
21
TOC: Regular v/s Not Regular
In the following question, Neither L1 is subset of L2, nor L2 is subset of L1, so i think their intersection should be disjoint and L1 INTERSECTION L2, should be phi which is a Regular language, hence, option (A) should be correct. The given solution:
asked
Dec 1, 2018
in
Theory of Computation
by
chauhansunil20th
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(
4.1k
points)

36
views
theoryofcomputation
regularlanguages
+1
vote
0
answers
22
Can't understand the intution behind the shortcut
let the ∑ = {0,1} ===> strings possible are should be Binary strings. No.of States in Minimal DFA that accepts, Decimal( Binary String ) = 0 mod n in ACE coaching institute, i learned that For Decimal( Binary String ) = 0 mod n i) if n ... String ) = 0 mod x or 0 mod y neither x divides y nor y divides x either x is divides y or y divides x
asked
Nov 30, 2018
in
Theory of Computation
by
Shaik Masthan
Veteran
(
50.4k
points)

92
views
minimalstateautomata
regularlanguages
0
votes
0
answers
23
Condition for regular language to be infinite
Given M = (Q,Σ,δ,q0,F) a DFA with n states. Prove: The language L(M) is infinite iff it contains a string with length t, where n ≤ t < 2n. Please provide a prove. I am not getting it from the resources available on the ... we can accept infinite no. of strings isn't it? Then why doesn't this condition suffice? Please point out where I am going wrong.
asked
Nov 30, 2018
in
Theory of Computation
by
MiNiPanda
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(
19.8k
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87
views
theoryofcomputation
finiteautomata
regularlanguages
0
votes
0
answers
24
Theory of Computation
For a binary string x = a0a1 · · · an−1 define val(x) to be the value of x interpreted as a binary number, where a0 is the most significant bit. More formally, val(x) is given by How many minimum states will be in a finite automaton that accepts exactly the set of binary strings x such that val(x) is divisible by either 4 or 5. i m getting 5 states. ??
asked
Nov 20, 2018
in
Theory of Computation
by
Abhisek Tiwari 4
Active
(
3.6k
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51
views
theoryofcomputation
finiteautomata
regularlanguages
+1
vote
1
answer
25
GATEBOOK2019TOC110
If $L$ is a regular language, which of the following is true? $L' = \{x_1x_3x_5 \ldots \mid x_0x_1x_2x_3x_4 \ldots \in L\}$ is non  regular $L'' = \{x_0x_2x_4 \ldots \mid x_0x_1x_2x_3x_4 \ldots \in L\}$ is non  regular Both $L'$ and $L''$ are nonregular Both $L'$ and $L''$ are regular
asked
Nov 12, 2018
in
Theory of Computation
by
GATEBOOK
Boss
(
13.5k
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131
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gb2019toc1
regularlanguages
0
votes
1
answer
26
GATEBOOK2019TOC116
Consider the DFA with states $\{0,1,2,3,4\},$ input alphabet set $\{0.1\},$ start state $0,$ final state $0,$ and transition function $\delta \left ( q,i \right ) = (q^2i) \mod 5 \mid i \in\{0,1\}. $The language accepted ... binary strings containing odd number of $0$'s Set of binary strings containing even number of $1$'s Set of binary strings containing odd number of $1$'s
asked
Nov 12, 2018
in
Theory of Computation
by
GATEBOOK
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(
13.5k
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80
views
gb2019toc1
finiteautomata
regularlanguages
+1
vote
1
answer
27
GATEBOOK2019TOC120
Let $L_1 = a^*b^*$ and $L_2 = \{ab\}.$ $L_3 = \text{Prefix}(L_1^* \cap L_2),$ where $\text{Prefix}(L) = \{u \mid uv \in L$ for some $v\}.$ Number of strings in $L_3$ is _______
asked
Nov 12, 2018
in
Theory of Computation
by
GATEBOOK
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(
13.5k
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126
views
gb2019toc1
regularlanguages
numericalanswers
0
votes
0
answers
28
RE for given FA
The correct regular expression for the below mentioned Finite Automata Do we have to have ca* as C is dead state,does dead state be a part of regular expression? The expression I am gettting is c*a(d*+ba*) as C state is dead state hence no need to consider it.Please Correct me.
asked
Nov 6, 2018
in
Theory of Computation
by
sripo
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1.3k
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55
views
theoryofcomputation
finiteautomata
regularexpressions
regularlanguages
0
votes
1
answer
29
Are these two languages equal?
L1=ab* L2=a(aa)*b(bb)* Are the languages equal if not what relation do they satisfy?
asked
Nov 6, 2018
in
Theory of Computation
by
sripo
Active
(
1.3k
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31
views
theoryofcomputation
regularlanguages
regulargrammar
0
votes
0
answers
30
This question is taken from a sample paper
Consider the following grammar G. Is this regular? S →EF E → a∈ F → abFac
asked
Nov 3, 2018
in
Theory of Computation
by
Piyush Agarwal 1
(
15
points)

14
views
finiteautomata
regularlanguages
regulargrammar
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