#include"iostream"
#include"iomanip"
using namespace std;
class fushu
{
float x,y;
public:
fushu(float a=0,float b=0)
{
x=a;
y=b;
}
void add(fushu &m,fushu &n)
{
x=m.x+n.x;
y=m.y+n.y;
disp();
}
void chengfa(fushu &m,fushu &n)
{
x=m.x*n.x-m.y*n.y;
y=m.x*n.y+n.y*n.x;
disp();
}
void disp()
{
cout<