C++AND UML习题及答案（给学生）(9)

int Ai; Ai=nLength*nWidth; return Ai; }

double Area_double() { double Ad; Ad=dLength*dWidth; return Ad; }

virtual ~Rect() { cout<<\ } private:

int nLength; int nWidth; double dLength; double dWidth; };

void main() { Rect R1(1,2); cout<Area_double()<