**what is ****deterministic finite automata?**

An automata which has finite states is called as finite automata and a finite automata which has input for every alphabet of language on each state is deterministic finite automata, because path for each alphabet is determined. Watch Video HERE!

Deterministic finite automata **dfa **rules are:

#### 1. Complete number of arrows:

If language has 2 alphabets then each state must have 2 arrows.

If language has 3 alphabets then each state must have 3 arrows.**It means the number of arrows on each state = number of alphabets of language.**

#### 2. Null Transition

**Dfa cannot have a null transition, **means In dfa we cannot put ^ on any arrow**.**

#### 3. Reject State:

**In dfa we may use reject state,** it is a non-final state from which we cannot go to anyother state thats why the string gets rejected**.**

#### How to make dfa in automata:

1. First make states for without star part of regular expression or for the required condition of language.2. Now, we have to complete arrows on each state, for that try to put loop on each state if it satisfies the condition of language.3.