#include<iostream>
#include<cmath>
using namespace std;
class Point //Point类声明
{
public:
Point(int xx=0, int yy=0) {
X=xx;Y=yy;
cout<<"Point构造函数被调用"<<endl;}
Point(Point &p);
~Point(){
cout<<"Point析构函数调用"<<endl;
}
int GetX() {return X;}
int GetY() {return Y;}
private:
int X,Y;
};
Point::Point(Point &p) //拷贝构造函数的实现
{
X=p.X;
Y=p.Y;
cout<<"Point拷贝构造函数被调用"<<endl;
}
//类的组合
class Line //Line类的声明
{
public: //外部接口
Line (Point xp1, Point xp2,int c);
Line (Line &);
~Line(){
cout<<"Line析构函数调用"<<endl;
}
double GetLen(){return len;}
int GetColor(){return color;}
private: //私有数据成员
Point p1,p2; //Point类的对象p1,p2
double len;
int color;
};
//组合类的构造函数
Line:: Line (Point xp1, Point xp2,int c)
:p1(xp1),p2(xp2)
{
cout<<"Line构造函数被调用"<<endl;
double x=double(p1.GetX()-p2.GetX());
double y=double(p1.GetY()-p2.GetY());
len=sqrt(x*x+y*y);
color=c;
}
//组合类的拷贝构造函数
Line:: Line (Line &Seg): p1(Seg.p1),p2(Seg.p2)
{
cout<<"Line拷贝构造函数被调用"<<endl;
len=Seg.len;
color=Seg.GetColor();
}
int main()
{
Point myp1(1,1),myp2(4,5); //建立Point类的对象
Line line(myp1,myp2,222); //建立Line类的对象
Line line2(line);//利用拷贝构造函数建立一个新对象
cout<<"The length of the line is:";
cout<<line.GetLen()<<endl;
cout<<"The color of the line is:";
cout<<line.GetColor()<<endl;
cout<<"The length of the line2 is:";
cout<<line2.GetLen()<<endl;
cout<<"The color of the line2 is:";
cout<<line2.GetColor()<<endl;
}
麻烦解读一下运行结果
