GATE CSE 2021 Set 2 Q19: Language that always has a minimal DFA with the same k states
- Theory of Computation
- 1 mark
- MCQ
- −1/3 if wrong
Question
Let be an arbitrary regular language accepted by a minimal DFA with states. Which one of the following languages must necessarily be accepted by a minimal DFA with states?
Try it: multiple choice: exactly one correct option
Show answer and explanation
Answer: C (official GATE 2021 final answer key)
Concept used: Complementing a complete DFA only swaps accepting and non-accepting states, so the number of states of the minimal DFA is unchanged.
First step: Swap final and non-final states of the minimal DFA for and ask whether any two states could become equivalent.
Full step-by-step solution
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Source: official GATE 2021 Set 2 CS question paper and final answer key, organised by IIT Bombay. Question paper · Answer key
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