struct node {
  void *item;
  uint item_size;
  struct node *next;
};

typedef struct node *NODEPTR;

void *m_alloc(void *tmp, int n)
{
  
  tmp = (void *)malloc(n);
  if (tmp == NULL) {
    fprintf(stderr, "ERRORE: memoria insufficiente.\n");
    exit (1);
  }

  return (tmp);
}    

void *find_end(node *lista){
  node *tmp;
  tmp=lista;
  while (tmp->next!=NULL) {
     tmp=tmp->next;
  }
  return tmp;
}