public async Task EvalTest()
{
RPN rpn = new RPN();
Console.Write("Type infix expression [ctrl+c to brake]: ");
string infix = "AX = 5 + 90";
string lol = rpn.Eval(infix).Content;
}
public static void TestMethod1()
{
RPN rpn = new RPN();
Console.Write("Type infix expression [ctrl+c to brake]: ");
string infix = Console.ReadLine();
Console.WriteLine("Result: {0}", rpn.Eval(infix).Content);
}