-- mancano i commenti


parse :: [Char] -> Bool


parse string = q1 string

q1 ('a':cs) = q2 cs || q4 cs

q1 _ = False

q2 ('b':cs) = q3 cs

q2 _ = False

q3 "b" = True

q3 ('c':cs) = q3 cs

q3 _ = False

q4 ('a':[]) = True

q4 _ = False