public static void Main(string[] args)
{
IExpression exp1 = new Add(new Value(1), new Value(2));
IExpression exp2 = new Mul(new Add(new Value(1), new Value(2)), new Value(2));
IExpression exp3 = new Sub(new Mul(new Add(new Value(1), new Value(2)), new Value(2)), new Value(1));
Console.WriteLine(exp1.Evaluate());
Console.WriteLine(exp2.Evaluate());
Console.WriteLine(exp3.Evaluate());
}
public void Mul_Add_1_And_2_And_3_Return_6()
{
IExpression exp2 = new Mul(new Add(new Value(1), new Value(2)), new Value(2));
Assert.AreEqual(6, exp2.Evaluate());
}