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Recent questions tagged regularexpressions
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2
answers
1
Doubt Regular Language and regular expressions
asked
Jul 16
in
Theory of Computation
by
abhiram144
(
51
points)

48
views
theoryofcomputation
regularexpressions
finiteautomata
regularlanguages
0
votes
1
answer
2
GATE  TOC Regular Languages & FA
Let L(r1)=(b*ab*ab*ab*)* & L(r2)=(b*ab*ab*)*. What is L(r1) Intersection L(r2)? a) (b*ab*ab*ab*)* b) (b*ab*ab*)* c) (b*ab*ab*)^6 d) (b*ab*ab*ab*ab*ab*ab*)* Please do explain also.
asked
Jul 15
in
Theory of Computation
by
Ashish Roy 1
(
17
points)

57
views
theoryofcomputation
regularlanguages
regularexpressions
finiteautomata
0
votes
1
answer
3
regular expressions
asked
Jul 8
in
Theory of Computation
by
once_2019
(
291
points)

65
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theoryofcomputation
regularexpressions
0
votes
1
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4
#Regular Expression
Which one of the Regular Expression given defines the same language as defined by R = (a + b)* (aa + bb) (a + b)* ? (a) (a (ba)* + b (ab)*) (a + b)* (b) (a (ba)* + b (ab)*)* (a + b)* (c) (a (ba)* (a + bb) + b (ab)* (b + aa)) (a + b)* (d) (a (ba)* (a + bb) + b (ab)* (b + aa)) (a + b)+
asked
Jul 8
in
Theory of Computation
by
himgta
Junior
(
747
points)

51
views
regularexpressions
0
votes
1
answer
5
Ullman
What will be the regular expression for the language consisting of all binary strings which have at most one pair of consecutive zeroes?
asked
Jul 6
in
Theory of Computation
by
Lakshay Kakkar
Junior
(
961
points)

72
views
regularexpressions
0
votes
1
answer
6
Language of strings not containing 101
Can someone show how we can systematically come up with regular expression for language not containing string 101 on alphabet {0,1} by first creating DFA and then converting it to regular expression?
asked
Jul 6
in
Theory of Computation
by
GateAspirant999
Active
(
2.6k
points)

58
views
theoryofcomputation
regularexpressions
0
votes
1
answer
7
Simplifying regular expressions
What is regex for the DFA: I am coming up with following two: 1. b*a(a+b)* and 2. b*a(b+ab*a)*+b*ab*a(ab*a+b)* Both seems to be correct to me. For X1, we have regex b*a(b+ab*a) For X2, we have regex b*ab*a(ab*a ... question: I want to know if I can simplify regex 2 to regex 1 by regex identities, but not by any other approach say by dfa minimization. Is it possible?
asked
Jul 1
in
Theory of Computation
by
GateAspirant999
Active
(
2.6k
points)

60
views
theoryofcomputation
regularexpressions
finiteautomata
regularlanguages
0
votes
1
answer
8
Regular Expressions
What is the language produced by.... null*(denoted by phi) doubt from youtube video here
asked
Jun 19
in
Theory of Computation
by
Kirandas R
(
67
points)

75
views
theoryofcomputation
regularexpressions
0
votes
0
answers
9
Test series
Can someone explain this problem? Thanks in advance
asked
Jun 17
in
Theory of Computation
by
Kalpataru Bose
(
339
points)

72
views
madeeasytestseries
testbooktestseries
theoryofcomputation
regularexpressions
+1
vote
3
answers
10
Theory of computation
asked
Jun 6
in
Theory of Computation
by
Prince Sindhiya
Active
(
1.2k
points)

92
views
regularexpressions
+1
vote
1
answer
11
Theory of computation
asked
Jun 6
in
Theory of Computation
by
Prince Sindhiya
Active
(
1.2k
points)

47
views
regularexpressions
0
votes
1
answer
12
WBUT 2011
Construct a NFA for $r=(11+0)^*(00+1)^*$
asked
May 27
in
Theory of Computation
by
Sourav_35
(
199
points)

89
views
nfa
regularexpressions
theoryofcomputation
0
votes
2
answers
13
Doubt .... Theory of Computation ..... Regular Expression
asked
May 21
in
Theory of Computation
by
abhiram144
(
51
points)

80
views
theoryofcomputation
regularexpressions
0
votes
1
answer
14
Doubt ..... Theory of Computing
find regular expression over $\{a,b\}$ corresponding to "set of strings containing Exactly $2a's$.". I have come up with two answers and are seeming Logically correct to me. Please correct me If I am wrong. 1. $b^* a b^* a b^*$  This ... $b$ In the middle of $2 a's$ and $2 a's$ at the end. I am wondering if both of them are correct. Thanks in advance.
asked
May 20
in
Theory of Computation
by
abhiram144
(
51
points)

62
views
theoryofcomputation
regularexpressions
0
votes
1
answer
15
Regular expression#previous year gate
Give a regular expression for the set of binary strings where every $0$ is immediately followed by exactly $k$ number of $1's$ and preceded by at least $k$ number of $1's$ ($k$ is a fixed integer).Choose the correct one out of two. $1^*1^k(01^k)^*1^*$ $1^*(1^k01^k)^*$
asked
May 20
in
Theory of Computation
by
MeghnaJain
(
9
points)

101
views
theoryofcomputation
regularexpressions
0
votes
0
answers
16
what is the regular expression and design dfa and nfa for arthimatic expression
asked
May 13
in
Theory of Computation
by
doaa
(
31
points)

89
views
finiteautomata
theoryofcomputation
regularexpressions
nfa
0
votes
0
answers
17
FA to Regular Expression: when no two a's and no two b's should come together
asked
May 9
in
Theory of Computation
by
surbhijain93
(
61
points)

102
views
theoryofcomputation
regularexpressions
finiteautomata
0
votes
1
answer
18
Peter Linz Chapter 4.3 Exercise Q.20
I don't think it will be regular . Had the language been uwwRv the expression could have been (a+b)*(aa+bb)(a+b)* as there is no restriction on w. Is it correct? and if it isn't regular, is it a CFL?
asked
May 4
in
Theory of Computation
by
Subham Nagar
Junior
(
601
points)

75
views
theoryofcomputation
regularlanguages
regularexpressions
0
votes
1
answer
19
Peter Linz Chapter 4
L = {a^n: n ≥ 2, is a prime number}. This is not a regular language. What about L*? Is it regular? Please explain.
asked
May 4
in
Theory of Computation
by
Subham Nagar
Junior
(
601
points)

63
views
theoryofcomputation
regularexpressions
regularlanguages
0
votes
1
answer
20
TOC question on Regular expresstion
Find length of string of minimum length on {0,1}* not in the language corressponding to the given RE 0^*(01^*)^* options are 1 2 3 None of these Is it asking to find the minimum length string and then length of it if yes then minimum length can be ... ans is 1 plzz rectify me if I have not understand the question properly second RE 1^*(0+10)^* options are 2 3 4 5
asked
May 1
in
Theory of Computation
by
sanju77767
(
153
points)

40
views
regularexpressions
+2
votes
2
answers
21
Regular Expressions
Can (ab* + b)* be written as (a + b)*.If so then how?
asked
Apr 7
in
Theory of Computation
by
Sourav_35
(
199
points)

212
views
regularexpressions
+2
votes
2
answers
22
Random
Let $'r'$ be a regular expression, then which of the following statements is/are TRUE for every $'r'$? $\qquad S1: \text{There exists 'x' which satisfies property } r + x =x$. $\qquad S1: \text{There exists 'x' which satisfies property } r .x =x$. $\text{S1 is FALSE, S2 is FALSE}$ $\text{S1 is FALSE, S2 is TRUE}$ $\text{S1 is TRUE, S2 is FALSE}$ $\text{S1 is TRUE, S2 is TRUE}$
asked
Mar 30
in
Theory of Computation
by
Shivani gaikawad
(
197
points)

88
views
theoryofcomputation
regularexpressions
+1
vote
1
answer
23
Gateforum booklet
asked
Mar 30
in
Theory of Computation
by
Prince Sindhiya
Active
(
1.2k
points)

72
views
regularexpressions
+2
votes
1
answer
24
Gateforum booklet
Which of the following is false? Regular sets are closed under substitution Regular sets are closed under homomorphism Regular sets are closed under inverse homomorphism Regular sets are closed under quotient with nonregular sets. iv) only iii) and iv) only iii) only None of these
asked
Mar 30
in
Theory of Computation
by
Prince Sindhiya
Active
(
1.2k
points)

42
views
regularexpressions
0
votes
2
answers
25
Peter linz exercise 3.1 qsn 20(c)
Give regular expression for all strings containing odd number of zeros on $\{0,1\}$
asked
Mar 21
in
Theory of Computation
by
Kakashi
(
17
points)

89
views
theoryofcomputation
regularexpressions
0
votes
1
answer
26
theory of computation
Let $L=\{w \in \{0,1\}^∗\mid \text{number of occurences of }(110)=\text{number of occurences of } (011)\}$ What is $L$?
asked
Mar 21
in
Theory of Computation
by
varunraj
Junior
(
677
points)

100
views
theoryofcomputation
regularexpressions
+1
vote
1
answer
27
Peter Linz Exercise 3.1 Question 28
Find a regular expression for all bit strings, with leading bit 1, interpreted as a binary integer, with values not between 10 and 30.
asked
Mar 15
in
Theory of Computation
by
Mk Utkarsh
Boss
(
13k
points)

131
views
theoryofcomputation
peterlinz
regularexpressions
0
votes
1
answer
28
Peter Linz Exercise 3.1 Question 27
Find a regular expression that denotes all bit strings whose value, when interpreted as a binary integer, is greater than or equal to 40.
asked
Mar 15
in
Theory of Computation
by
Mk Utkarsh
Boss
(
13k
points)

131
views
theoryofcomputation
peterlinz
regularexpressions
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