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Recent questions tagged regularexpressions
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1
Doubt .... Theory of Computation ..... Regular Expression
asked
2 days
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in
Theory of Computation
by
abhiram144
(
25
points)

47
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theoryofcomputation
regularexpressions
0
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1
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2
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
2 days
ago
in
Theory of Computation
by
abhiram144
(
25
points)

36
views
theoryofcomputation
regularexpressions
0
votes
1
answer
3
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
2 days
ago
in
Theory of Computation
by
MeghnaJain
(
7
points)

66
views
theoryofcomputation
regularexpressions
0
votes
0
answers
4
what is the regular expression and design dfa and nfa for arthimatic expression
asked
May 13
in
Theory of Computation
by
doaa
(
31
points)

42
views
finiteautomata
theoryofcomputation
regularexpressions
dfa
nfa
0
votes
0
answers
5
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
(
31
points)

70
views
theoryofcomputation
regularexpressions
finiteautomata
0
votes
1
answer
6
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
(
507
points)

58
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theoryofcomputation
regularlanguages
regularexpressions
0
votes
1
answer
7
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
(
507
points)

48
views
theoryofcomputation
regularexpressions
regularlanguages
0
votes
1
answer
8
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
(
151
points)

29
views
regularexpressions
+2
votes
2
answers
9
Regular Expressions
Can (ab* + b)* be written as (a + b)*.If so then how?
asked
Apr 7
in
Theory of Computation
by
Sourav_35
(
79
points)

200
views
regularexpressions
+2
votes
2
answers
10
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
(
87
points)

80
views
theoryofcomputation
regularexpressions
+1
vote
1
answer
11
Gateforum booklet
asked
Mar 30
in
Theory of Computation
by
Prince Sindhiya
(
367
points)

63
views
regularexpressions
+2
votes
1
answer
12
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
(
367
points)

34
views
regularexpressions
0
votes
2
answers
13
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)

77
views
theoryofcomputation
regularexpressions
0
votes
1
answer
14
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
(
667
points)

82
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theoryofcomputation
regularexpressions
+1
vote
1
answer
15
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
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(
12.3k
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95
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theoryofcomputation
peterlinz
regularexpressions
0
votes
1
answer
16
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
(
12.3k
points)

65
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theoryofcomputation
peterlinz
regularexpressions
0
votes
1
answer
17
Peter linz Exercise 3.1 Question 17 d
$\sum = \left \{ 0,1 \right \}$ Give a regular expression for all strings having at least two occurrences of the substring 00. (Note that with the usual interpretation of a substring, 000 counts two such occurences)
asked
Mar 15
in
Theory of Computation
by
Mk Utkarsh
Boss
(
12.3k
points)

65
views
theoryofcomputation
peterlinz
regularexpressions
0
votes
2
answers
18
Peter linz Exercise 3.1 Question 16.3
Give regular expression for the following language on $\sum = \left \{ a,b,c \right \}$ All strings that contain at least one occurrence of each symbol in $\sum$
asked
Mar 14
in
Theory of Computation
by
Mk Utkarsh
Boss
(
12.3k
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68
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theoryofcomputation
peterlinz
regularlanguages
regularexpressions
+2
votes
1
answer
19
Peter Linz Exercise 3.1 Question 10
Give a regular expression for L = $\left \{a^{n}b^{m};n\geq 1,m \geq 1,nm \geq3 \right \}$
asked
Mar 14
in
Theory of Computation
by
Mk Utkarsh
Boss
(
12.3k
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178
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theoryofcomputation
peterlinz
regularexpressions
+2
votes
1
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20
#TOC Doubt  Regular expressions
Part A: Given : (bab*ab*)* How can it be interpreted as: 1.((b+ab*)ab*)* 2.(b+(ab*ab*))* 3.((b+a)b*ab*)* Part B: 1.What will be its NFA ? 2.Can we draw a direct MINIMAL DFA for such questions?
asked
Mar 13
in
Theory of Computation
by
ashishgateashish
(
93
points)

118
views
regularexpressions
finiteautomata
nfa
dfa
theoryofcomputation
+1
vote
0
answers
21
Dfa to regex
please verify the regex
asked
Mar 12
in
Theory of Computation
by
Mk Utkarsh
Boss
(
12.3k
points)

48
views
theoryofcomputation
finiteautomata
regularexpressions
+1
vote
1
answer
22
ISRO exam
Cfg for regular expression $(ab+a)^* (aa+b)$
asked
Mar 9
in
Theory of Computation
by
Prince Sindhiya
(
367
points)

69
views
theoryofcomputation
regularexpressions
+1
vote
0
answers
23
Regular Expression
What is the regular expression of $L = \{ s \in L$ $i$ = no of $1$ in string $s$ $j$ = no of $0$ in string $s$ $i+j$ is odd $\}$ ???
asked
Mar 4
in
Theory of Computation
by
Dharmesh Gusai
(
19
points)

75
views
regularexpressions
theoryofcomputation
finiteautomata
regularlanguages
+1
vote
2
answers
24
Doubt
What is identity for regular expressions ?
asked
Feb 10
in
Theory of Computation
by
Angkit
Active
(
3.7k
points)

57
views
regularexpressions
+3
votes
1
answer
25
CMI2017A01
The regular expression $(a^*+b)^*$ is equivalent to which of the following regular expressions: $a^*b^*$ $(a^*b+b)^*$ $(a+b^*)^*$ $(a^*b)^*$
asked
Feb 5
in
Theory of Computation
by
Tesla!
Boss
(
15.9k
points)

212
views
theoryofcomputation
regularexpressions
cmi2017
0
votes
1
answer
26
Regular expression
S > AaB A > aC  $\epsilon$ B > aB  bB  $\epsilon$ C > aCb  $\epsilon$ Is the regular expression for the above is this: a(a + b)* a ( a* + b* )* ?
asked
Feb 1
in
Theory of Computation
by
Tuhin Dutta
Loyal
(
7.8k
points)

134
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theoryofcomputation
regularexpressions
0
votes
3
answers
27
Regular Expression
Can I write a* + b* = (a + b)* ????
asked
Jan 31
in
Theory of Computation
by
MRINMOY_HALDER
(
97
points)

125
views
regularexpressions
theoryofcomputation
identifiers
0
votes
0
answers
28
#TOC Doubt
L = anbm / n,m>=1 What type pf Language is this? Also, please tell are n,m are independent or dependent i.e can we have like n=2 and m=3 or both n,m have to have same values!?
asked
Jan 30
in
Theory of Computation
by
iarnav
Loyal
(
6.9k
points)

44
views
theoryofcomputation
finiteautomata
regularexpressions
regulargrammar
+2
votes
1
answer
29
Made easy test
(a^n)^m b^n where n>=0 and m>1 is a) regular b) cfl c) csl d) none
asked
Jan 29
in
Theory of Computation
by
♥_Less
Junior
(
977
points)

73
views
madeeasytestseries
regularexpressions
regularlanguages
contextfreelanguage
contextsensitive
+3
votes
1
answer
30
Concatenation: REG / REC / DCFL / CFL?
Let A is the language where no of 'a' is greater than no of 'b' and B is the language where no of 'b' is greater than no of ‘a’ the language A.B is ______________ a. Regular b. DCFL but not Regular c. CFL but not DCFL d. REC but not DCFL
asked
Jan 27
in
Theory of Computation
by
Tuhin Dutta
Loyal
(
7.8k
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90
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theoryofcomputation
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dcfl
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