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The Golden Chain. ε NFA NFA DFA REGEX. Regular Expressions . Computations in a semi-ring. Given a weighted graph, find the shortest path connecting any two vertices Given a graph, find its transitive closure Given a finite automaton, find the REGEX describing its language.
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The Golden Chain εNFA NFA DFA REGEX
Computations in a semi-ring • Given a weighted graph, find the shortest path connecting any two vertices • Given a graph, find its transitive closure • Given a finite automaton, find the REGEX describing its language
From DFA ro Regex: Example Will need:
The pumping lemma • Cannot prove that a language is regular • It MIGHT be able to confute that a language is regular • It does not state that in any regular language every sufficiently long string z contains a repeated term, i.e., z =xyyw