List.h

/** List abstract class. */
template <typename ItemType> class List {
public:
  virtual int size() const = 0;
  virtual ItemType &get(int i) = 0;
  virtual const ItemType &get(int i) const = 0;
  virtual void insert(const ItemType &x, int i) = 0;
  virtual ItemType remove(int i) = 0;
  virtual void addFirst(const ItemType &x) = 0;
  virtual void addLast(const ItemType &x) = 0;
  virtual ItemType &getFirst() = 0;
  virtual ItemType &getLast() = 0;
  virtual const ItemType &getFirst() const = 0;
  virtual const ItemType &getLast() const = 0;
  virtual ItemType removeFirst() = 0;
  virtual ItemType removeLast() = 0;
}