A machine is represented by states Q, input alphabet Σ, transition function δ,…
2025
A machine is represented by states Q, input alphabet Σ, transition function δ, initial state q₀ and final state F. The machine accepts all the strings over Σ = {a, b}, which start and ended with any combination of all alphabet and abb works/lies as substring in all the strings to be accepted.
For the above specified passage, which of the following is DFA for the language represented/accepted by machine?
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Deterministic Finite Automaton (DFA) that accepts strings containing the substring "abb".
Why Option C is correct: It is the only graph among the choices that represents a valid, complete DFA for the given condition. It traces the sequence a→b→b (moving through states 1, 2, 3, 4) and includes the necessary loopbacks and transitions for all inputs. Although a minimal DFA for "abb" typically requires only 4 states, Option C is a valid (though non-minimal) construction that satisfies the DFA definition.
Why others are incorrect:
Option A is an NFA (Non-Deterministic Finite Automaton), not a DFA. This is because State 1 has two transitions for the input 'a' (one looping back to itself and one moving to State 2).
Option B appears to be an incomplete DFA, as State 3 lacks a defined transition for input 'a'.
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