送交者: steven 于 2005-2-11, 21:12:52:
回答: Help!!!!!!!!! Urgent!!!!!!!!! 由 红雨 于 2005-2-11, 20:06:55:
const_expr. The class has two operands, the second one may be null, and one operator. Each operand is a instance of expr, a const_expr eval return the value of two constant operands operated on the operator. The expr eval the return values of operand-> evel() operated on the operator.