using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

    }

    new Component("a+b-c*d");

}

​

public class Component{

    Component(string blabla) {

        if(tryParse(blabla)) {

            value = double.parse(blabla);

            return;

        }

        //split at + or -

        String[] bits = blabla.Split('+');

        A = new Component(bits[0]);

        B = new Component(bits.skip(1).aggregate());

    }

    double value;

    Component A;

    Component B;

    Operator operators;

    double getValue() {

        if(value!=null) return value;

        return A.getValue() + B.getValue();

    }

}

​

public enum Operator {

    ADD,

    MINUS,

    DIVIDE,

    POWER,

    TIMES

}