- Trending Categories
- Data Structure
- Networking
- RDBMS
- Operating System
- Java
- MS Excel
- iOS
- HTML
- CSS
- Android
- Python
- C Programming
- C++
- C#
- MongoDB
- MySQL
- Javascript
- PHP
- Physics
- Chemistry
- Biology
- Mathematics
- English
- Economics
- Psychology
- Social Studies
- Fashion Studies
- Legal Studies

- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who

# How to convert Regular expression to Finite Automata?

To convert the regular expression (RE) to Finite Automata (FA), we can use the Subset method.

Subset method is used to obtain FA from the given RE.

**Step 1**− Construct a Transition diagram for a given RE by using Non-deterministic finite automata (NFA) with ε moves.**Step 2**− Convert NFA with ε to NFA without ε.**Step 3**− Convert the NFA to the equivalent Deterministic Finite Automata (DFA).

Some basic RE are as follows −

**Case 1** − For a regular expression ‘a’, we can construct FA as shown below −

**Case 2** − For a regular expression ‘ab’ we can construct FA, as given below −

**Case 3** − For a regular expression (a+b) we can construct FA as follows −

**Case 4** − For a RE (a+b)*, We can construct FA as mentioned below −

- Related Articles
- How to generate regular expression from finite automata?
- How to convert the finite automata into regular expressions?
- Design finite automata from a given regular expression.
- Explain the relationship between Finite Automata and Regular Expression.
- What is the conversion of a regular expression to finite Automata (NFA)?
- Find out the Regular expression for the given finite automata
- What are the regular expressions to finite automata?
- Generate a Regular Expression for a Finite Automata with state elimination method
- Construct a Finite Automata for the regular expression ((a+b)(a+b))*.
- Find the regular expression for the given Finite automata with state elimination method
- Can we convert a non-deterministic finite automata into a deterministic finite Automata?
- What is finite automata?
- C program to simulate Nondeterministic Finite Automata (NFA)
- Explain Arden’s theorem to convert DFA to Regular Expression
- Efficient Construction of Finite Automata

Advertisements