//**************************************
//
//      link class implement file
//
// PROJECT NAME: LINK
// 
// YOUR NAME: XYZ
// YOUR ID: 1234
// YOUR EMAIL: xyz@cs.ucr.edu
//
//**************************************

#include "link.h"


//**************************************************
// Implement functions in class "element"  
//**************************************************

void element::setValue(element_type v) 
{ 
  value = v; 
}; 

element_type element::getValue() 
{ 
  return value; 
}; 

element::element() 
{ 
  //init value and next 
  value = 0; 
  next = NULL; 
}; 

element::element(element_type v) 
{ 
  element();  //init  
  setValue(v); //set value
}; 

element *  element::getNext(){ 
  return next ; 
} 

void element::makeNext(element *a){ 
  next = a;  //set next pointer to "a"
}; 

//  ~element(); 
  
element * element::print() 
{ 
  cout << getValue(); //print the value of current element
  return next; 
} 


void list::addElement(element_type val) 
{ 
  element *tmp; 
  
  tmp = new element(val); // create a new element with the value equal to "val"
  tmp->makeNext(head);    // link the "head" element as the next of the new element
  head = tmp;             // change the "head" pointer to the new element
}; 


element *list::popElement(){ 
  element * tmp; 
  tmp = head;             // get the head element
  head = head->getNext(); // change the "head" pointer to the next element
  return tmp; 
} 



//**************************************************
// Implement the functions in class list  
//************************************************** 
list::list() 
{ 
  head = NULL; 
}; 


// print out all the elements in the list
void list::print(){ 
  element *current; 
  
  cout << "LIST " ; 
  current = head; 
  while( current != NULL) 
    { 
      current =  current->print(); 
      cout << " "; 
    } 
  cout << " END"; 
}