l2u3

struct List
{
  List()
  {
    first = nullptr;
  }

  void add_node(int value)
  {


    if(first == nullptr)
    {
      Node* _new{new Node{value}};
      first = _new;
    }
    else
    {
      Node* curr{first->next};

      while(curr->next != nullptr)
      {
        curr = curr->next;
      }
      Node* _new{new Node{value, curr->next}};
      curr->next = _new;
    }
  }

  Node* first;
};

struct Node
{
  Node(int _value, Node* _next = nullptr)
   :
  {
    value{_value};
    next{_next};
  }

  void set_next(Node* _next)
  {
    next = _next;
  }

  int value;
  Node* next;
};

int main()
{
  List l{};

  l.add_node(5);
  l.add_node(9);

}