定义Point,Circle,Cylinder类.用友元求(friend)圆面积,圆柱体体积.
问题描述：
定义Point,Circle,Cylinder类.用友元求(friend)圆面积,圆柱体体积.
答
#include using namespace std;const double PI = 3.141592653;class Point{public:\x05double X;\x05double Y;public:\x05Point() :X(0),Y(0){};\x05Point(double x,double y) :X(x),Y(y){};};class Circle :public...