/******************************************************************************
*	
*	
*	File:     ou2.cc
*	
*	
*	$Log$
******************************************************************************/

#include <iostream.h>
const int nil = 0;
typedef int Type;  //Här bör du nog ändra!!

#ifndef __GNUG__
enum bool {false,true};
#endif

class Node {
friend class List;
private:
  Type val;
  Node* next;
  Node (Type value, Node* item = 0) {val = value; next = item;}
};

class List {
public:
  Type first() {return list->val;}
  void rest(); 
  void concat(Type);
  bool is_empty() {return (bool)(list == nil);}
  List() {list = nil;}
  ~List() ;
  void traverse(void (*p_func)(Type&)); 
  void add_last(Type);  // Till denna metod saknas kod !!!!!!
  void append(List& l); //Denna metod beror av add_last (som ju tyvaerr ...)
private:
  Node* list;
};

  
void List::concat(Type val) {
  Node* pt = new Node(val, list);
  list = pt;
}

void List::rest() {
  Node* pt = list;
  list = list -> next;
  delete pt;
}

List::~List() {
  Node* pt = list;
  while (pt) {
    Node* tmp = pt;
    pt = pt -> next;
    delete tmp;
  }
}

void List::traverse(void (*p_func)(Type&)){
  Node* pt = list;
  while (pt) {
    (*p_func)(pt->val);
    pt = pt -> next;
  }
}

void List::append(List& l) {
  Node  *pt =  l.list;
  while (pt) {
    add_last(pt -> val);
    pt = pt -> next;
  }
}