public IOperand Minus(IOperand rhs)
{
if (!(rhs is LongOperand))
throw new RPN_Exception("Argument invalid in LongOperand.Minus : rhs");
LongOperand oprResult = new LongOperand("Result", Type.GetType("System.Int64"));
oprResult.Value = (long)this.Value - (long)((Operand)rhs).Value;
return oprResult;
}
public IOperand Multiply(IOperand rhs)