36 questions
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How do the kleene plus operators apply here? [duplicate]
(cd+)+?
I have cd+ to {cd, cdd, cddd, ...} but I do not understand how to apply the + from the parenthesis.
I saw that if it is like (d*)* then it is same as d* but here its not just d* in it but c ...
- reputation score 31
Score of 2
1 answer
2974 views
How to apply Kleene star on automata?
I know how to apply Kleene star on language but I'm not sure how would I apply it to DFA or NFA. I'm pretty sure it would need to be epsilon NFA with initial state that is final and final states might ...
- reputation score 379
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1 answer
318 views
Order in Kleene star operation?
Every example I had seen with Kleene star operations over languages show the expansion in order so I was wondering, does Kleene star operation requires ordering in the language?
For example, given the ...
- reputation score 410
Score of 0
1 answer
375 views
Using PCRE2 regex with repeating groups to find email addresses
I need to find all email addresses with an arbitrary number of alphanumeric words, separated through a period. To test the regex, I'm using the website https://regex101.com/.
The structure of a valid ...
- reputation score 5
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1163 views
A DFA for Kleene star operation
What would be the highest number of states a DFA would have for a language L*? Is it possible to define a worst-case scenario here?
- reputation score 69
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1 answer
740 views
Regex allow asterisk(*) only once time and in the end [closed]
I want to pass only the strings like this:
abc*
123*
abc 123*
abc-123abc*
I don't want to pass strings like those:
- abc**
- abc*123
- *abc
The asterisk must be in the end and only once time.
...
- reputation score 93
Score of 0
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438 views
Implementing Kleene star operator * (sort of) in C program
For any user input string A ,with at least one instance of the star operator *,verify that input string B can be produced by A. For example: go*s can produce the strings goes,goners,goals etc.
I can't ...
- reputation score 23
Score of 1
2 answers
334 views
How to use a kleene star operator (*) or it's variant (+) with variables in sparql?
I have some working code for getting all the ancestors of a term in a hierarchy.
Following:
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>
PREFIX skos-xl: <http://www.w3.org/...
- reputation score 2277
Score of 0
1 answer
158 views
Kleene star semantics and set comparison
Say we have two languages L1 and L2, is the following condition below considered false?
(L1L2)* = L1*L2*
I'm assuming this because say:
Leftside of condition:
L1 = {a,b}
L2 = {c,d}
C = L1.L2
C = {...
- reputation score 787
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2 answers
638 views
String length after kleen's closure in finite-autometa theory
Note: Not sure if this is the correct site for this question. I found other finite-autometa theory questions here, so posting here.
Suppose a language is defined over two letters
L1 = { aa , b }
...
- reputation score 1210
Score of 1
2 answers
70 views
Does the kleene-star's potence 0 fulfill a disjunction?
Does the regular expression X•(Y*+Z) accept the word X?
I would say it does, as Y=ε should fulfill the disjunction, but I'm not sure.
- reputation score 1174
Score of 1
0 answers
469 views
Best way to implement Kleene star operation in Java
How can I implement the Kleene star operator to determine the Kleene closure up to a specific level?
- reputation score 154
Score of 6
1 answer
1308 views
Why can't the Kleene closure construction for an NFA be simplified?
Most sources, such as http://www.cs.may.ie/staff/jpower/Courses/Previous/parsing/node5.html, suggest that the Kleene closure be constructed with 4 nodes.
Why can't it be constructed with just 2, as ...
- reputation score 416
Score of 5
2 answers
9220 views
Deterministic Finite Automaton of Kleene Star
I read that every Non-deterministic Finite Automaton (NFA) can be transferred into a Deterministic Finite Automaton (DFA). Can this be done for kleene star regex, say a*?
Above is the NFA for a*.
- reputation score 3907
Score of 10
1 answer
15371 views
Automata Regular expression - difference between concatenation & union
What is the difference between the following regular expressions?
(a U b)* and (ab)*
Difference between union and concatenation ?
which of the above regex accepts strings in which 'a' is always ...
- reputation score 117
