C++ Class Definition Implementing add(), subtract() and multiply() for Integer class

 
#include <iostream>
 
class Integer/* www  .  j  a v a 2 s. c o  m*/
{
private:
  int n;
 
public:
  Integer(int m = 0);
  Integer(Integer& obj);                 // Copy constructor
  int compare(const Integer& obj) const; // Compare function with reference paramter
  int getValue() {return n;}
  void setValue(int m){ n = m; }
  void show();
 
  Integer* add(const Integer& obj);
  Integer* add(int m);
  Integer* subtract(const Integer& obj);
  Integer* subtract(int m);
  Integer* multiply(const Integer& obj);
  Integer* multiply(int m);
 
};
using std::endl;
 
// Copy constructor
Integer::Integer(Integer& obj) : n(obj.n)
{
  std::cout << "Object created by copy constructor." << std::endl;
}
 
// Constructor
Integer::Integer(int m) : n(m)
{
  std::cout << "Object created." << std::endl;
}
 
Integer* Integer::add(const Integer& obj)
{
  n += obj.n;
  return this;
}
 
Integer* Integer::subtract(const Integer& obj)
{
  n -= obj.n;
  return this;
}
 
Integer* Integer::multiply(const Integer& obj)
{
  n *= obj.n;
  return this;
}
 
void Integer::show() {
  std::cout << "Value is " << n << std::endl;
}
 
// Compare function with reference parameter
int Integer::compare(const Integer& obj) const {
  if(n < obj.n)
    return -1;
  else if(n==obj.n)
    return 0;
  return 1;
}
 
int main()
{
  Integer a {4};
  Integer b {6};
  Integer c {7};
  Integer d {8};
  Integer x {5};
 
  Integer result {a};                       // Set result object as copy of a
  Integer* pResult = &result;
  std::cout << "Result is "
            << pResult->multiply(x)->add(b)->multiply(x)->add(c)->multiply(x)->add(d)->getValue()
            << std::endl;
}