#include <iostream>
 
using namespace std;
 
struct List
{
  List *next = 0;
};
 
List & operator ++ (List &x, int)
{
  x = *x.next;
  return x;
}
 
int main()
{
  List *lst = new List();
  lst->next = new List();
 
  cout << lst << ' ' << lst->next << endl;
 
  (*lst)++;
  cout << lst << ' ' << lst->next << endl;
 
  // Это упадёт
  //(*lst)++;
  //cout << lst << endl;
 
  List lst2;
  lst2.next = new List();
 
  cout << &lst2 << ' ' << lst2.next << endl;
 
  lst2++;
  cout << &lst2 << ' ' << lst2.next << endl;
 
  return 0;
}

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