/** Namespace for containers.  
    This class is used as a namespace for global identifiers related to the
    implementation of containers.  It is inherited by all container objects.  */

class GCont
{
private:
  // --- Base class for list nodes
  struct Node
  {
    Node *next;
    Node *prev;
  };
  // -- Class for list nodes
  template <class T> struct ListNode : public Node
  { 
    T val;
    ListNode();
    ListNode(const T &ref) : val(ref) { } ;
  };
  // -- Class for map nodes showing the hash
  struct HNode : public Node
  {
    unsigned int hashcode;
  };
  // -- Class for map nodes showing the hash and the key
  template <class K> struct SetNode : public HNode
  {
    K key;
    SetNode(const K &key) : key(key) { } ;
  };
  // -- Class for map nodes with everything
  template <class K, class T> struct MapNode : public SetNode<K>
  {
    T val;
    MapNode(const K &key) : SetNode<K>(key) { } ;
  };
};