2.5. Adding to a Linked List
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2.5. Adding to a Linked List 

void BidderCollection::add (const Bidder& value)

could be implemented as 

void BidderCollection::add (const Bidder& value)
//  Adds this bidder
//Pre: getSize() < getMaxSize()
{
  list.addToEnd (value);
  ++size;
}

or 

void BidderCollection::add (const Bidder& value)
//  Adds this bidder
//Pre: getSize() < getMaxSize()
{
  list.addInOrder (value);
  ++size;
}

addToEnd 

template <typename Data>
struct LListHeader {

  LListNode<Data>* first;


  LListHeader();

  void addToFront (const Data& value);
  void addToEnd (const Data& value);

  // Add value in sorted order.
  //Pre: all existing values are already ordered
  void addInOrder (const Data& value);
     ⋮

template <typename Data>
void LListHeader<Data>::addToEnd (const Data& value)
{ 
  LListNode<Data>* newNode = new LListNode<Data>(value, NULL);
  if (first == NULL)
    {
      first = newNode;
    }
  else
    {
      // Move to last node 
      LListNode<Data>* current = first;
      while (current->next != NULL)
        current = current->next;
      
      // Link after that node
      current->next = newNode;
    }
}

E.g. Suppose we have a list containing "Adams", "Baker", & "Davis", and we are going to add "Chen". 

template <typename Data>
void LListHeader<Data>::addToEnd (const Data& value)
{ 
  LListNode<Data>* newNode = new LListNode<Data>(value, NULL);
 

template <typename Data>
void LListHeader<Data>::addToEnd (const Data& value)
{ 
  LListNode<Data>* newNode = new LListNode<Data>(value, NULL);
  if (first == NULL)
    {
      first = newNode;
    }
  else
    {
      // Move to last node 
      LListNode<Data>* current = first;
 

template <typename Data>
void LListHeader<Data>::addToEnd (const Data& value)
{ 
  LListNode<Data>* newNode = new LListNode<Data>(value, NULL);
  if (first == NULL)
    {
      first = newNode;
    }
  else
    {
      // Move to last node 
      LListNode<Data>* current = first;
      while (current->next != NULL)
        current = current->next;
 

template <typename Data>
void LListHeader<Data>::addToEnd (const Data& value)
{ 
  LListNode<Data>* newNode = new LListNode<Data>(value, NULL);
  if (first == NULL)
    {
      first = newNode;
    }
  else
    {
      // Move to last node 
      LListNode<Data>* current = first;
      while (current->next != NULL)
        current = current->next;

      // Link after that node
      current->next = newNode;
}

addInOrder 

template <typename Data>
void LListHeader<Data>::addInOrder (const Data& value)
{
  if (first == NULL)
    first = new LListNode<Data>(value, NULL);
  else 
    {
      LListNode<Data>* current = first;
      LListNode<Data>* prev = NULL;
      while (current != NULL && value > current->data)
        {
          prev = current;
          current = current->next;
        }
      // Add between prev and current
      if (prev == NULL)
        addToFront (value);
      else
        addAfter (prev, value);
    }
}

Again, suppose we have a list containing "Adams", "Baker", & "Davis", and we are going to add "Chen". 

template <typename Data>
void LListHeader<Data>::addInOrder (const Data& value)
{
  if (first == NULL)
    first = new LListNode<Data>(value, NULL);
  else 
    {
      LListNode<Data>* current = first;
      LListNode<Data>* prev = NULL;


template <typename Data>
void LListHeader<Data>::addInOrder (const Data& value)
{
  if (first == NULL)
    first = new LListNode<Data>(value, NULL);
  else 
    {
      LListNode<Data>* current = first;
      LListNode<Data>* prev = NULL;
      while (current != NULL && value > current->data)
        {
          prev = current;
          current = current->next;
        }


template <typename Data>
void LListHeader<Data>::addInOrder (const Data& value)
{
  if (first == NULL)
    first = new LListNode<Data>(value, NULL);
  else 
    {
      LListNode<Data>* current = first;
      LListNode<Data>* prev = NULL;
      while (current != NULL && value > current->data)
        {
          prev = current;
          current = current->next;
        }
      // Add between prev and current
      if (prev == NULL)
        addToFront (value);
      else
        addAfter (prev, value);
    }
}

addAfter 

template <typename Data>
void LListHeader<Data>::addAfter (LListNode<Data>* afterThis, const Data& value)
{
  LListNode<Data>* newNode = new LListNode<Data>(value, afterThis->next);
  afterThis->next = newNode;
}


template <typename Data>
void LListHeader<Data>::addAfter (LListNode<Data>* afterThis, const Data& value)
{
  LListNode<Data>* newNode = new LListNode<Data>(value, afterThis->next);


template <typename Data>
void LListHeader<Data>::addAfter (LListNode<Data>* afterThis, const Data& value)
{
  LListNode<Data>* newNode = new LListNode<Data>(value, afterThis->next);
  afterThis->next = newNode;
}

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