对象参数问题

[hailun]

#include<iostream.h>
class cpoint
{
int x,y;
public:
cpoint(){x=0,y=0;}
cpoint(int vx,int vy)
{x=vx;y=vy;}
cpoint(cpoint &pt)
{
x=pt.x;//pt.x什么意思呀
y=pt.y;
cout<<"调用复制构造函数cpoint(cpoint &)!\n";
}
void print(){cout<<x<<'\t'<<y<<'\n';}
};
void main()
{
cpoint pt1(100,200);
pt1.print();
cpoint pt2(pt1);//对象作为实参要调用自定义拷贝构造函数是这样吗?
pt2.print();
cpoint pt3=pt1;//这个为什么也要调用拷贝构造函数呢?
pt3.print();
cout<<"标志...\n";
pt3=pt2;//此行是不是多余呀
}

[xiaocai0001]

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