Non Deterministic Automata

1. Non Deterministic Automata Courtesy Costas Busch - RPI

2. Nondeterministic Finite Accepter (NFA) Alphabet = Courtesy Costas Busch - RPI

3. Nondeterministic Finite Accepter (NFA) Alphabet = Two choices Courtesy Costas Busch - RPI

4. Nondeterministic Finite Accepter (NFA) Alphabet = Two choices No transition No transition Courtesy Costas Busch - RPI

5. First Choice Courtesy Costas Busch - RPI

6. First Choice Courtesy Costas Busch - RPI

7. First Choice Courtesy Costas Busch - RPI

8. First Choice All input is consumed “accept” Courtesy Costas Busch - RPI

9. Second Choice Courtesy Costas Busch - RPI

10. Second Choice Courtesy Costas Busch - RPI

11. Second Choice No transition: the automaton hangs Courtesy Costas Busch - RPI

12. Second Choice Input cannot be consumed “reject” Courtesy Costas Busch - RPI

13. An NFA accepts a string: when there is a computation of the NFA that accepts the string AND all the input is consumed and the automaton is in a final state Courtesy Costas Busch - RPI

14. Example is accepted by the NFA: “accept” “reject” because this computation accepts Courtesy Costas Busch - RPI

15. Rejection example Courtesy Costas Busch - RPI

16. First Choice Courtesy Costas Busch - RPI

17. First Choice “reject” Courtesy Costas Busch - RPI

18. Second Choice Courtesy Costas Busch - RPI

19. Second Choice Courtesy Costas Busch - RPI

20. Second Choice “reject” Courtesy Costas Busch - RPI

21. An NFA rejects a string: when there is no computation of the NFA that accepts the string: • All the input is consumed and the • automaton is in a non final state OR • The input cannot be consumed Courtesy Costas Busch - RPI

22. Example is rejected by the NFA: “reject” “reject” All possible computations lead to rejection Courtesy Costas Busch - RPI

23. Rejection example Courtesy Costas Busch - RPI

24. First Choice Courtesy Costas Busch - RPI

25. First Choice No transition: the automaton hangs Courtesy Costas Busch - RPI

26. First Choice Input cannot be consumed “reject” Courtesy Costas Busch - RPI

27. Second Choice Courtesy Costas Busch - RPI

28. Second Choice Courtesy Costas Busch - RPI

29. Second Choice No transition: the automaton hangs Courtesy Costas Busch - RPI

30. Second Choice Input cannot be consumed “reject” Courtesy Costas Busch - RPI

31. is rejected by the NFA: “reject” “reject” All possible computations lead to rejection Courtesy Costas Busch - RPI

32. Language accepted: Courtesy Costas Busch - RPI

33. Lambda Transitions Courtesy Costas Busch - RPI

34. Courtesy Costas Busch - RPI

35. Courtesy Costas Busch - RPI

36. (read head does not move) Courtesy Costas Busch - RPI

37. Courtesy Costas Busch - RPI

38. all input is consumed “accept” String is accepted Courtesy Costas Busch - RPI

39. Rejection Example Courtesy Costas Busch - RPI

40. Courtesy Costas Busch - RPI

41. (read head doesn’t move) Courtesy Costas Busch - RPI

42. No transition: the automaton hangs Courtesy Costas Busch - RPI

43. Input cannot be consumed “reject” String is rejected Courtesy Costas Busch - RPI

44. Language accepted: Courtesy Costas Busch - RPI

45. Another NFA Example Courtesy Costas Busch - RPI

46. Courtesy Costas Busch - RPI

47. Courtesy Costas Busch - RPI

48. Courtesy Costas Busch - RPI

49. “accept” Courtesy Costas Busch - RPI

50. Another String Courtesy Costas Busch - RPI