generics

how to add two integer and float variables?

class genericclass
    {


        private T a;
        private T b;

        public void sum(T val1, T val2)

        {
            Console.WriteLine(" sum is "+ (val1 + val2));
        }


    }

    class Program
    {
        static void Main(string[] args)
        {

            genericclass gcint1= new genericclass;
            gcint1.sum(2, 3);
            genericclass gcfloat1=new genericclass;
            gcfloat1.sum(2.0, 3.0);

        }
    }