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#ifndef H_orderedListType
#define H_orderedListType
#include "linkedList.h"
using namespace std;
template <class Type>
class orderedLinkedList: public linkedListType<Type>
{
public:
bool search(const Type& searchItem) const;
//Function to determine whether searchItem is in the list.
//Postcondition: Returns true if searchItem is in the list,
// otherwise the value false is returned.
void insert(const Type& newItem);
//Function to insert newItem in the list.
//Postcondition: first points to the new list, newItem
// is inserted at the proper place in the list, and
// count is incremented by 1.
void insertFirst(const Type& newItem);
//Function to insert newItem at the beginning of the list.
//Postcondition: first points to the new list, newItem is
// inserted at the beginning of the list, last points to the
// last node in the list, and count is incremented by 1.
void insertLast(const Type& newItem);
//Function to insert newItem at the end of the list.
//Postcondition: first points to the new list, newItem is
// inserted at the end of the list, last points to the
// last node in the list, and count is incremented by 1.
void deleteNode(const Type& deleteItem);
//Function to delete deleteItem from the list.
//Postcondition: If found, the node containing deleteItem is
// deleted from the list; first points to the first node
// of the new list, and count is decremented by 1. If
// deleteItem is not in the list, an appropriate message
// is printed.
};
template <class Type>
bool orderedLinkedList<Type>::search(const Type& searchItem) const
{
bool found = false;
nodeType<Type> *current; //pointer to traverse the list
current = this-> first; //start the search at the first node
while (current != NULL && !found)
if (current->info >= searchItem)
found = true;
else
current = current->link;
if (found)
found = (current->info == searchItem); //test for equality
return found;
}//end search
template <class Type>
void orderedLinkedList<Type>::insert(const Type& newItem)
{
nodeType<Type> *current; //pointer to traverse the list
nodeType<Type> *trailCurrent; //pointer just before current
nodeType<Type> *newNode; //pointer to create a node
bool found;
newNode = new nodeType<Type>; //create the node
newNode->info = newItem; //store newItem in the node
newNode->link = NULL; //set the link field of the node
//to NULL
if (this->first == NULL) //Case 1
{
this->first = newNode;
this->last = newNode;
this->count++;
}
else
{
current = this->first;
found = false;
while (current != NULL && !found) //search the list
if (current->info >= newItem)
found = true;
else
{
trailCurrent = current;
current = current->link;
}
if (current == this->first) //Case 2
{
newNode->link = this->first;
this->first = newNode;
this->count++;
}
else //Case 3
{
trailCurrent->link = newNode;
newNode->link = current;
if (current == NULL)
this->last = newNode;
this->count++;
}
}//end else
}//end insert
template<class Type>
void orderedLinkedList<Type>::insertFirst(const Type& newItem)
{
insert(newItem);
}//end insertFirst
template<class Type>
void orderedLinkedList<Type>::insertLast(const Type& newItem)
{
insert(newItem);
}//end insertLast
template<class Type>
void orderedLinkedList<Type>::deleteNode(const Type& deleteItem)
{
nodeType<Type> *current; //pointer to traverse the list
nodeType<Type> *trailCurrent; //pointer just before current
bool found;
if (this->first == NULL) //Case 1
cout << "Cannot delete from an empty list." << endl;
else
{
current = this->first;
found = false;
while (current != NULL && !found) //search the list
if (current->info >= deleteItem)
found = true;
else
{
trailCurrent = current;
current = current->link;
}
if (current == NULL) //Case 4
cout << "The item to be deleted is not in the "
<< "list." << endl;
else
if (current->info == deleteItem) //the item to be
//deleted is in the list
{
if (this->first == current) //Case 2
{
this->first = this->first->link;
if (this->first == NULL)
this->last = NULL;
delete current;
}
else //Case 3
{
trailCurrent->link = current->link;
if (current == this->last)
this->last = trailCurrent;
delete current;
}
this->count--;
}
else //Case 4
cout << "The item to be deleted is not in the "
<< "list." << endl;
}
}//end deleteNode
#endif
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