对于这样一种类与类之间的关系，我们希望为其编写“深拷贝”。两个类的定义如下：

class Point {    int x;    int y;};class Polygon : public Shape {    Point *points;};

 

　　1. 构造函数

//构造函数Polygon(const Point &p) : _point(new Point){　　this->_point->x = p.x;　　this->_point->y = p.y;}

　　2. 拷贝构造函数

//拷贝构造Polygon(const Polygon &p) : _point(new Point){    this->_point->x = p._point->x;    this->_point->y = p._point->y;}

　　3. 赋值构造函数

//赋值操作符void operator= (const Polygon &rhs){    this->_point->x = rhs._point->x;    this->_point->y = rhs._point->y;}

 

　　全部代码 & 测试用例

#include 
      
       using namespace std;struct Shape {    int no; //形状编号};struct Point {    int x;    int y;    Point(int x, int y) : x(x), y(y) {}    Point() = default;};struct Polygon :public Shape {    Point *_point;    //构造函数    Polygon(const Point &p) : _point(new Point)    {        this->_point->x = p.x;        this->_point->y = p.y;    }    //拷贝构造    Polygon(const Polygon &p) : _point(new Point)    {        this->_point->x = p._point->x;        this->_point->y = p._point->y;    }    //赋值操作符    void operator= (const Polygon &rhs)    {        this->_point->x = rhs._point->x;        this->_point->y = rhs._point->y;    }    ~Polygon()    {        delete this->_point;    }};int main(){    Point x1(1, 2);    Polygon p1(x1);    Polygon p2 = p1;    Polygon p3(p2);    p1 = p2;    return 0;}
      

 

　　内存中变量地址

 

　　p1 . _ponit 内存地址 0x002c0cb8

　　p2 . _point 内存地址 0x002c0cf0

　　p3 . _point 内存地址 0x002c0d28

　　（都是不相同的内存地址）

 

成功