static void Main(string[] args)
{
//Pass request
LeaveRequest Request = new LeaveRequest();
Request.EmpName = "Ajay";
Request.LeaveDays = 25;
// Create oobject with Abstraction
ILeaveRequestHandler hr = new HR();
ILeaveRequestHandler pm = new PeojectManager();
ILeaveRequestHandler TL = new TeamLead();
//Define hierarchy
TL.NextHandler = pm;
pm.NextHandler = hr;
hr.NextHandler = null;
// call from low level request. If pass then it will success based on request other wise it send to next object
TL.HandleRequest(Request);
Console.ReadLine();
}