//-----------------------------------------------------------------
//
// pointers.cpp
//
// Illustrating basic things about pointers
// 
// written by: Simon Parsons
// modified  : 5th March 2010
//
//-----------------------------------------------------------------

#include <iostream>
using namespace std;

//----------------------------------------------------------------
//
// point

// The class point represents a location in a set of cartesian coordinates.
//
// It has two data members, an x and a y value.
 
class point {

public:
  double x, y;

  void print();
  void set(double, double);
}; 

// Print the values 

void point::print(){
  cout << "(" << x << "," << y << ")\n";
}
 
// Set the values.

void point::set( double u, double v ) {
  x = u;
  y = v;
}

// End of point

//----------------------------------------------------------------
//
// Main program

int main() {

  // Declare an integer an integer array, and a pointer to an integer.

  int a;
  int b[5] = {1, 2, 3, 4, 5};

  int* aptr;

  // Make the pointer point to the integer and then use it to manipulate
  // the value of the integer.

  aptr = &a;
  *aptr = 6;
  
  cout << "a has value: " << a << endl;

  (*aptr)++;

  cout << "a has value: " << a << endl;

  *aptr = *aptr + 1;

  cout << "a has value: " << a << endl;

  // New use a pointer to an object

  point p;
  point* pptr;

  // Make the pointer point to the object

  pptr = &p;

  // Access the members of the object

  (*pptr).set(1.2,3.4);
  pptr->print();
}

// end of main()