Characterizing DFA languages
How can we characterize DFA languages ?
Expert
It will be illustrated that the set of languages recognized by FA is closed under:
– union “C = (A ∪ B)”– concatenation “C = (A ° B)”– star “C = A* ”Meaning: if A and B are the languages recognized by a DFA, then C is a language recognized by the DFA• union “C = (A ∪ B)”(A ∪ B) = {x : x ∈ A or x ∈ B or both}
• concatenation “C = (A ° B)”(A ° B) = {xy: x ∈ A and y ∈ B}
• star “C = A* ” (note: ε always in A*)A* = {x1 x2 x3…xk: k ≥ 0 and each xi ∈ A}
What do you understand by the term Finite Automata ?
Proof the theorem that the class of regular languages is closed under union; that is, if L1 is recognized by a NFA and L2 is recognized by a NFA, then L1 υ L2 is recognized by a NFA as well.
Let s1 and s2 be two strings of lengths m and n respectively. By definition, a superstring of s1 and s2 is one which contains s1 and s2 as substrings. Give a dynamic programming algorithm to compute a shortest superstring of t
Let REGEXP be the language of valid regular expressions over {a, b}. That is, REGEXP is the set of all strings over the symbols Σ= {a, b, (,), U,*, ^} that are valid regular expressions. For example, the string “a (a U b)" is in REGEXP, whereas the string
Explain briefly NFA operation with example.
Give an algorithm that, given a grammar G = (V, Σ, R, S), decides whether the grammar G can derive the empty string.
Explain in detail about Homology Modelling
Describe the theorem that a language L is recognized by a DFA if and only if L is illustrated by a regular expression.
What is the formal definition of DFA ?
18,76,764
1954740 Asked
3,689
Active Tutors
1425839
Questions Answered
Start Excelling in your courses, Ask an Expert and get answers for your homework and assignments!!