语言！ Definition 2.3.1.9.Let S be an alphabet.Every set L is called a lan- guage over The complement of the language L according to is LC=∑*-L. A language can be used to describe a set of consistent input instances of an algorithmic problem. For instance,the set of all representations of formu- lae in CNF as a set of words over Logic or the set {u#u2#...#um ui E 10,1)m,m E NN}as the set of representations of all directed graphs over 10,1,#are examples of such languages.语言！