Delete an array of objects : object array « Class « C++ Tutorial

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C++ Tutorial » Class » object array 
9.33.9.Delete an array of objects
#include <iostream>
#include <cstdlib>
#include <new>
using namespace std;

class Point {
  int x, y;
public:
  Point() {x = y = 0;}
  Point(int px, int py) {
    x = px;
    y = py;
  }

  void show() {
    cout << x << " ";
    cout << y << "\n";
  }

  void *operator new(size_t size);
  void operator delete(void *p);

  void *operator new[](size_t size);
  void operator delete[](void *p);
};

// new overloaded relative to Point.
void *Point::operator new(size_t size)
{
void *p;

  cout << "In overloaded new.\n";
  p =  malloc(size);
  if(!p) {
    bad_alloc ba;
    throw ba;
  }
  return p;
}

// delete overloaded relative to Point.
void Point::operator delete(void *p)
{
  cout << "In overloaded delete.\n";
  free(p);
}

// new overloaded for Point arrays.
void *Point::operator new[](size_t size)
{
  void *p;

  cout << "Using overload new[].\n";
  p =  malloc(size);
  if(!p) {
    bad_alloc ba;
    throw ba;
  }
  return p;
}

// delete overloaded for Point arrays.
void Point::operator delete[](void *p)
{
  cout << "Freeing array using overloaded delete[]\n";
  free(p);
}

int main()
{
  Point *p1, *p2;
  int i;

  try {
    p1 = new Point (1020)// allocate an object
  catch (bad_alloc xa) {
    cout << "Allocation error for p1.\n";
    return 1;;
  }

  try {
    p2 = new Point [10]// allocate an array
  catch (bad_alloc xa) {
    cout << "Allocation error for p2.\n";
    return 1;;
  }

  p1->show();

  for(i=0; i<10; i++)
    p2[i].show();

  delete p1; // free an object
  delete [] p2; // free an array

  return 0;
}
In overloaded new.
Using overload new[].
10 20
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
In overloaded delete.
Freeing array using overloaded delete[]
9.33.object array
9.33.1.Create an array of objects
9.33.2.An array of objects: call its method
9.33.3.Initialize an array of objects without referencing the constructor directly
9.33.4.Initialize an array of objects by referencing the constructor directly
9.33.5.Object array of derived classes
9.33.6.Allocate an array of objects using new operator
9.33.7.An array of pointers to objects
9.33.8.An array on the heap
9.33.9.Delete an array of objects
9.33.10.allocates and frees an object and an array of objects of type loc.
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