Regular expression to NFA (Nondeterministic Finite Automata)

I am trying to describe here how to convert a Regular Expression to Nondeterministic Finite Automata (NFA) with example and details procedure.

1. Converting regular expression to nfa 1

2. Daffodil International University Submitted By Niloy Biswas (171-35-225) Submitted to Bikash Kumar Paul Lecturer, Department of SWE Daffodil International University 2 DATE: 15 April 2019

3. regular expression A regular expression (regex) describe a set of possible input string. A sequence of characters that defines a search pattern. If you have a regular expression parsing and searching program, You can search for all string that match some patters within some text. 3

4. Converting regular expression to nfa Example -1 Construct Nondeterministic Finite Automata (NFA) for regular expression b* + ab Step 1 We start by drawing the diagram : S f b* + ab 4

5. Step 2 S f b* + ab b* ab S f b* ab Step 3 a b 5

6. Step 4 S f b b* a b Final step S f b b* a b ϵ ϵ 6

7. Example -2 An NFA that recognize the string “and” , & “any” 7

8. Example -3 Construct an NFA that recognize ((a | b) | cd) 8

9. References www.jflap.org en.wikipedia.org web.stanford.edu www.stackoverflow.com www.quara.com 9

10. Thank You 10