Here I am giving the solutions for the previous questions , 
Sorry that forgot to give the sample for the output for the previous program.

here's the answer(Code)

#include<iostream.h>

#include<conio.h>

static int count;

class point

{

float a,b;

public:

point()

{

a=b=0;

}

void get()

{   count++;

cout<<"Enter the X coordinate of point "<<count<<"\t";

   cin>>a;

   cout<<"Enter the Y coordinate of point "<<count<<"\t";

   cin>>b;

   }

 void add(point obj1,point obj2)

 {

  this->a=obj1.a+obj2.a;

  this->b = obj1.b+obj2.b;

   }

   void show()

   {

   cout<<"The X coordinate of final point is \t"<<a;

   cout<<"\nthe Y coordinate of final point is\t"<<b;

   }

   };

   void main ()

   {

   point obj1,obj2,obj3;

   obj1.get();

   cout<<"\n\n";

   obj2.get();

   obj3.add(obj1,obj2);

   cout<<"\n\n";

   obj3.show();

   getch();

   }

Sample output: