[PDF] (a+b)* regular expression language

( a + b )* corresponds to the set of all strings over the alphabet {a, b}. a*b* corresponds to the set of strings consisting of zero or more a's followed by zero or more b's. a*b+a* corresponds to the set of strings consisting of zero or more a's followed by one or more b's followed by zero or more a's.
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  • What is the difference between A *+ B * and AB )* in regular expression?

    So, a+b means [ab] or ab , thus (a+b)* means any string of length 0 or more, containing any number of a s and b s in any order. Likewise, (a*b*)* also means any string of length 0 or more, containing any number of a s and b s in any order. The two expressions are different ways of expressing the same language.7 fév. 2020

  • What is 0 * 1 * regular language?

    0*1* denotes the subset of the above language consisting only of all those strings having any number of 0's followed by any number of 1's. Thus the string 101 belongs to the former but does not belong to the latter.

  • What is the equation for a regular expression?

    X + Y is a Regular Expression corresponding to the language L(X) ? L(Y) where L(X+Y) = L(X) ? L(Y).
  • () denotes a capturing group. [a-z0-9] -- One character that is in the range of a-z OR 0-9. (a-z0-9) -- Explicit capture of a-z0-9 . No ranges. a -- Can be captured by [a-z0-9] .
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