Regular expression to ∈-NFA
Prerequisite – Finite Automata Introduction, Designing Finite Automata from Regular Expression (Set 1)
∈-NFA is similar to the NFA but have minor difference by epsilon move. This automaton replaces the transition function with the one that allows the empty string ∈ as a possible input. The transitions without consuming an input symbol are called ∈-transitions.
Attention reader! Don’t stop learning now. Practice GATE exam well before the actual exam with the subject-wise and overall quizzes available in GATE Test Series Course.
Learn all GATE CS concepts with Free Live Classes on our youtube channel.
In the state diagrams, they are usually labeled with the Greek letter ∈. ∈-transitions provide a convenient way of modeling the systems whose current states are not precisely known: i.e., if we are modeling a system and it is not clear whether the current state (after processing some input string) should be q or q’, then we can add an ∈-transition between these two states, thus putting the automaton in both states simultaneously.
Common regular expression used in make ∈-NFA:
Example: Create a ∈-NFA for regular expression: (a/b)*a
Refer for – Conversion from NFA to DFA, Minimization of DFA
