Implementation code
#include “ItemType.h” // unsorted.h
. . .
template <class ItemType>
class UnsortedType
{
public : // LINKED LIST IMPLEMENTATION
UnsortedType ( ) ;
~UnsortedType ( ) ;
void MakeEmpty ( ) ;
bool IsFull ( ) const ;
int LengthIs ( ) const ;
void RetrieveItem ( ItemType& item, bool& found ) ;
void InsertItem ( ItemType item ) ;
void DeleteItem ( ItemType item ) ;
void ResetList ( );
void GetNextItem ( ItemType& item ) ;
private :
NodeType<ItemType>* listData;
int length;
NodeType<ItemType>* currentPos;
} ;
#include “itemtype.h”
template <class ItemType>
UnsortedType<Itemtype>::UnsortedType ( ) // constructor
// Pre: None.
// Post: List is empty.
{
length = 0 ;
listData = NULL;
}
template <class ItemType>
int UnsortedType<Itemtype>::LengthIs ( ) const
// Post: Function value = number of items in the list.
{
return length;
}
template <class ItemType>
void UnsortedType<ItemType>::RetrieveItem( ItemType& item, bool& found )
// Pre: Key member of item is initialized.
// Post: If found, item’s key matches an element’s key in the list
// and a copy of that element has been stored in item; otherwise,
// item is unchanged.
{ bool moreToSearch ;
NodeType<ItemType>* location ;
location = listData ;
found = false ;
moreToSearch = ( location != NULL ) ;
while ( moreToSearch && !found )
{ if ( item == location->info ) // match here
{ found = true ;
item = location->info ;
}
else // advance pointer
{ location = location->next ;
moreToSearch = ( location != NULL ) ;
}
}
}
template <class ItemType>
void UnsortedType<Itemtype>::InsertItem ( ItemType item )
// Pre: list is not full and item is not in list.
// Post: item is in the list; length has been incremented.
{
NodeType<Itemtype>* location ;
// obtain and fill a node
location = new NodeType<Itemtype> ;
location->info = item ;
location->next = listData ;
listData = location ;
length++ ;
}
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