// Linklist.cpp

#include <stdlib.h>
#include <iostream.h>

class Node{
  private:
    int number;
    Node *link;
  public:
    Node();
    Node(int);
    Node(int, Node *);
    ~Node();
    int get_number();
    Node *get_link();
    void set_number(int);
    void set_link(Node *);
};

// default constructor
Node::Node(){
  number = 0;
  link = NULL;
}

// constructor with one argument
Node::Node(int num){
  number = num;
  link = NULL;
}

// primary constructor
Node::Node(int num, Node *l){
  number = num;
  link = l;
}

// destructor
Node::~Node(){
}

// accessor function for number
int Node::get_number(){
  return number;
}

// accessor function for link
Node * Node::get_link(){
  return link;
}

// mutator function for number
void Node::set_number(int n){
  number = n;
}

// mutator function for link
void Node::set_link(Node *l){
  link = l;
}

class Linklist{
  private:
    int numItems;
    Node *list;
  public:
    Linklist();
    ~Linklist();
    get_numItems() const;
    int is_empty();
    int getdata();
    void fill_list();
    Node *get_node();
    void reverse();
    void print_list();
  private:
    void reverse_list(Node *&);
};

// default constructor
Linklist::Linklist(){
  numItems = 0;
  list = NULL;
}

// destructor
Linklist::~Linklist(){
  Node * p = list;
  while (list != NULL){
    list = list->get_link();
    delete p;
    p = list;
  }
  list = NULL;
}

void Linklist::fill_list(){
  Node *temp;
  int flag = 1;
  int data;

  numItems = 0;
  list = get_node();   	// put first node in list
  numItems++;

  // fill rest of list
  while(flag){
    cout << "Enter an integer or 999 to quit: ";
    cin >> data;
    if(data != 999){
      temp = new Node(data,list);
      list = temp;
      numItems++;
    }
    else{
      flag = 0;
    }
  }
}

// accessor for numItems
int Linklist::get_numItems() const {
  return numItems;
}

// returns true if list is empty
int Linklist::is_empty(){
  return (list == NULL);
}

int Linklist::getdata(){
  int data;

  cout<< "Enter an integer: ";
  cin >> data;
  return data;
}

Node * Linklist::get_node(){
  Node *temp = new Node(getdata(),NULL);
  return temp;
}

void Linklist::reverse_list(Node * &init){
  Node *q = NULL;
  Node *p = init;
  init = NULL;
  while(p != NULL){
    q = p;
    p = p->get_link();
    q->set_link(init);
    init = q;
  } 
}
void Linklist::print_list(){
  Node *p = list;

  cout << "list -> ";
  while (p){
    cout << p->get_number();
    cout << " -> ";
    p = p->get_link();
  }
  cout << endl;
}

void Linklist::reverse(){
  reverse_list(list);
}

main(){
  Linklist *front = new Linklist;

  front->print_list();
  front->reverse();
  front->print_list();
  front->fill_list();
  front->print_list();
  front->reverse();
  front->print_list();
  cout << "List contains " << front->get_numItems();
  cout << " elements." << endl;
  return 0;
}