using System;

        public class student{

            private int id;

            public void setid(int ID){

                if(ID <= 0){

                throw new Exception("ID sholuld be zero or less");

                }

    else {

    id = ID;

    }

            }

    public int getid(){

         return id;

    }

        }

​

public class Program

{

    public static void Main()

    {

    student s1 = new student ();

        s1.setid(91312864);

        Console.WriteLine("id = {0}", s1.getid());

    }

}