##### Some important uses of DFA and NFA

Example 1:

let us say we have to make a Finite Automata such that** second character from left is a**

**This can be done using DFA**

and Σ={a,b}

then L={ba,aa,aab,bab ....etc}

So no of states here is: **n+ 2**

**Example 2**: Finite Automata such that** second character from right is a.**

**Solution: **To do this we need NFA, it can be done using DFA but it takes a lot of time.

what we have done is :

first, we made NFA then we convert that NFA into DFA, in DFA we have four states.