public void FalseExample3()
        {
            Negation neg = new Negation(new Disjunction(A, new Negation(C)));

            Assert.False(neg.Is_NNF());
        }
        public void FalseExample2()
        {
            Negation neg = new Negation(new Conjunction(A, B));

            Assert.False(neg.Is_NNF());
        }