##### 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.