Construct a DFA, that accepts string 'ab' over ∑={a,b}

SOLUTION:

∑={a,b}

L = {ab}

Ø  So DFA can be Q={ q₀ , q₁ , q₂},∑={a,b}, q₀={ q₀},F={q₂} and δ is given by the table

1)Transition diagram:

   2)Transition Table:

Present State	Next State
	Input a	Input b
à q0	q1	D
q1	D	q2
* q2	D	D
D	D	D

  3)Transition function:

δ( q₀, a)= q₁     ,δ (q₀,b)= D  

            δ( q₁, a)= D     ,δ (q₁,b)= q₂   

δ( q₂, a)= D     ,δ (q₂,b)= D

δ( D, a)= D      ,δ (D, b)= D