阅读下列说明和C++代码,填写程序中的空(1)~(6),将解答写入答题纸的对应栏内。 【说明】
以下C++代码实现一个简单绘图工具,绘制不同形状以及不同颜色的图形。部分类及其关系如图6-1所示。
【C++代码】
#include #include usingnamespacestd; classDrawCircle { /* 绘制圆形,抽象类 */ public: (1) ; /* 定义参数为intradius, int x, int y */ virtual ~ DrawCircle() { } }; classRedCircle : publicDrawCircle { /* 绘制红色圆形 */ public: voiddrawCircle( int radius, int x, int y ) { cout << "DrawingCircle[red,radius: " < cout << ",x: " < } }; classGreenCircle : publicDrawCircle { /* 绘制绿色圆形 */ public: voiddrawCircle( int radius, int x, int y ) { cout << "DrawingCircle[green,radius: " < cout << ",x: " < } }; classShape { /* 形状,抽象类 */ protected: (2); public: Shape( DrawCircle * drawCircle ) { this->drawCircle = drawCircle; } virtual ~ shape() { } public: virtualvoiddraw() = 0; }; classCircle : publicShape { /* 圆形 */ private: int x, y, radius; public: Circle( int x, int y, int radius, DrawCircle * drawCircle ) (3) { this->x = x; this->y = y; this->radius = radius; } public: voiddraw() { drawCircle->(4); } }; intmain() { Shape *redCircle = newCircle( 100, 100, 10, (5) ); /* 绘制红色圆形 */ Shape *greenCircle = newCircle( 100, 100, 10, (6) ); /* 绘制绿色圆形 */ redCircle->draw(); greenCircle->draw(); return0; }