#include <iostream>

using namespace std;

struct date
{ int day, month, year; };

void f(int x)
{ cout << "  This is the int version, (" << x << ")\n"; }

void f(date * p)
{ cout << "  This is the pointer version, ";  
  if (p == NULL)
    cout << "(NULL)\n";
  else
    cout << "(" << p->day << ", " << p->month << ", " << p->year << ")\n"; }

int main()
{ date * today = new date;
  today->day = 24;
  today->month = 1;
  today->year = 2023;

  cout << "Calling f(1234):\n";
  f(1234);

  cout << "Calling f(today):\n";
  f(today);

  cout << "Calling f(NULL):\n";
  f(NULL);

  cout << "Calling f(nullptr):\n";
  f(nullptr); }