#include <iostream>
#include <stdio.h>
#include <string.h>
using namespace std;
class operation
{
public:
	void set(double,double);
	void show();
	void add(operation,operation);
	void subtract(operation,operation);
	void multiply(operation,operation);
	void divide(operation,operation);
         operation();
private:
	double x;
	double y;
};

void operation::set(double a,double b)
{x=a;y=b;}
void operation::show()
{cout<<"x="<<x<<endl<<"y="<<y<<endl;
}
void operation::add(operation op1,operation op2)
{x=op1.x+op2.x;
y=op1.y+op2.y;
}
void operation::subtract(operation op1,operation op2)
{x=op1.x-op2.x;
y=op1.y-op2.y;
}
void operation::multiply(operation op1,operation op2)
{x=op1.x*op2.x-op1.y*op2.y;
y=op2.x*op2.y+op1.y*op2.x;
}
void operation::divide(operation op1,operation op2)
{x=(op1.x*op2.x+op1.y*op2.y)/(op2.x*op2.x+op2.y*op2.y);
y=(op1.y*op2.x+op1.x*op2.y)/(op2.x*op2.x+op2.y*op2.y);
}
 operation::operation()
{x=0.0;
y=0.0;
}


int main()
{
	operation op1,op2,op3;
	double x,y;
	op1.show();
	cout<<"input a and b:";
	cin>>x>>y;
	op1.set(x,y);
	cout<<"input c and d:";
	cin>>x>>y;
	op2.set(x,y);
	
	op3.add(op1,op2);
	cout<<"add result:";
	op3.show();
	op3.subtract(op1,op2);
	cout<<"subtract result:";
	op3.show();
	op3.multiply(op1,op2);
	cout<<"multiply result:";
	op3.show();
	op3.divide(op1,op2);
	cout<<"divide result:";
	op3.show();
	return 0;
}