#include
using namespace std;
class TwoCord
{
int x,y;
public:
TwoCord(int xx,int yy)
{
X=XX;
y=yy;
}
_______（1）_________(const TwoCord &c1,const TwoCord&c2)
{
__________（2）________
}
void display()
{
cout<<(*<
}；
int main()
{
TwoCord cl(1,2),c2(3,4);
cl=c1+c2;
c1.display();
return ();
}
【正确答案】：(1)friend TwoCord operator+【2分】
(2)return TwoCord(c1.x+c2.x,cl.y+c2.y);【2分】