public static AddClass1 operator -(AddClass1 op1, AddClass1 op2)
{
AddClass1 obj = new AddClass1();
obj.val = op1.val * op2.val;
return(obj);
}
static void Main(string[] args)
{
AddClass1 op1 = new AddClass1(); op1.val = 3;
AddClass1 op2 = new AddClass1(); op2.val = 2;
AddClass1 op3 = op1 - op2;
Console.WriteLine("op1+op2 = {0}", op3.val);
}