25 votes 25 votes We require a four state automaton to recognize the regular expression $(a\mid b)^*abb$ Give an NFA for this purpose Give a DFA for this purpose Theory of Computation gatecse-2002 theory-of-computation finite-automata normal descriptive + – Kathleen asked Sep 15, 2014 edited May 15, 2018 by Milicevic3306 Kathleen 4.2k views answer comment Share Follow See all 0 reply Please log in or register to add a comment.
Best answer 37 votes 37 votes NFA for regular expression $(a+b)^*abb$ and its equivalent $\textsf{DFA}$ will be as follows: Praveen Saini answered Mar 9, 2015 edited May 31, 2021 by Arjun Praveen Saini comment Share Follow See all 12 Comments See all 12 12 Comments reply Show 9 previous comments svas7246 commented Jun 26, 2021 reply Follow Share @Praveen Saini for The DFA here there is (a+b)∗ theres is an expression for b but how is it justified for a* 0 votes 0 votes Aman Lakher commented Dec 27, 2021 reply Follow Share in option A ,this NFA is for end with abb. in option B, we can directly draw dfa for end with abb. if we convert nfa to dfa , it will take much time. 0 votes 0 votes ꧁༒☬ĿọŗԀ 🆂🅷🅸🆅🅰☬༒꧂ commented Oct 15, 2023 reply Follow Share @svas7246As u can see clearly atleast one a and 2 b’s are required to accept the string so if first a comes it goes to q1 state and after that any number of a comes it will remain same in q1 state and after that when 2 b’s comes it goes to final state. 0 votes 0 votes Please log in or register to add a comment.