摘要：
class BooleanExp{public: // Interface. virtual bool Evaluate() const = 0;};class AndExp : public BooleanExp{ // data. BooleanExp &m_booleanExpA, &m_booleanExpB;public: AndExp(BooleanExp &booleanExpA, BooleanExp &booleanExpB) : m_booleanExpA(booleanExpA), m_booleanExpB(booleanExpB) {} 阅读全文
