module HW22a where
import DFA

-- |Construction showing that regular languages are closed under intersection. 
-- Assumes M1 and M2 have the same input alphabet.
-- (intersectDFA M1 M2) should return a DFA accepting the intersection of the languages of M1 and M2

intersectDFA :: DFA st1 -> DFA st2 -> DFA ... -- specify the type of states of the output DFA
intersectDFA (qs1, sigma, delta1, q1, inF1) (qs2, sigma2, delta2, q2, inF2) | sigma2 == sigma = 
  ... -- give a DFA for the intersection of the languages of the two input DFAs