using System;

using org.matheval;

public class Program

{

    public static void Main()

    {

        Expression expression = new Expression("IF(time>8, (HOUR_SALARY*8) + (HOUR_SALARY*1.25*(time-8)), HOUR_SALARY*time)");

        //bind variable

        expression.Bind("HOUR_SALARY", 10);

        expression.Bind("time", 9);

        //eval

        Decimal salary = expression.Eval<Decimal>();    

        Console.WriteLine(salary);

    }

}