// null example

#include <iostream>

using namespace std;


void IsNull (int * p)
{
  if (p)
    cout<<"Pointer is not NULL"<< endl;
  else
    cout<<"Pointer is NULL"<< endl;
}
 
int main()
{
  int * p;
  int i;
 
  p = NULL;
  IsNull(p);
  p = &i;
  IsNull(&i);
  IsNull(p);
  IsNull(NULL);
 
  getchar();
  return 0;
}