How would I find the language for the following regular expressions over the alphabet {a, b}? aUb* (ab*Uc)
Assuming you have a a set E = {a,b}, and you have a superset E* consisting of all possible combinat开发者_如何学编程ions of a, and b in E. How do you construct an expression for a String that has numb
I want to validate i开发者_C百科f a certain attribute is a valid regex. Is there some direct built in type in xml schema maybe xs:regex?
Several implementations of regular expressions differ from each other in subtle ways which is the source of much confusion when I try to use them.
I have a regular expression that was the output of a computer program.It has things like (((2)|(9)))* which a human would undoubtedly write as
Let L = {a^f(m) | m >= 1 } where f: Z^+ -> Z^+ is monotone increasing and complies that for all element n in Z^+ there is an m开发者_运维知识库 belonging to Z^+ such that f(m+1) - f(m) >= n.
The intersection of a context-free language and a regular language is always context-free but context-free languages are not closed under set intersection. Could anyone explain why both theorems are t
Maybe I have missed something, but what are wrong with this regular expresion? var str = \"lorem ipsum 12345 dolor\";
I have the following question from a past exam paper: I am struggling to formalise their definitions within the necessary 15 word limit. So far I have:
I have a compiler question. Determin开发者_开发技巧e whether {(ab)^n | n >= 0} is a regular language?
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