/*
Linked List Declaration
Author: Aqua Lo
Department of Bio-Engineering
South China University of Technology
Please use under permission!
*/
#ifndef __LLink
#define __LLink
#include <iostream>
#include "Link.h"
using namespace std;
using namespace aqua;
namespace aqua
{
template <typename T> class LList: public Link<T>
{
private:
Link<T>* head;
Link<T>* tail;
Link<T>* fence;
//Pointer to list header
//Pointer to last Element in list
//Last element on left side
int leftcnt,rightcnt;
//Size of left partition
//Size of right partition
void init() //Initializtion routine
{
fence = tail = head = new Link<T>;
leftcnt = rightcnt = 0;
}
void removeall() //Return link nodes to free store
{
while(head != NULL)
{
fence = head;
head = head->next;
delete fence;
}
}
public:
LList() { init(); }
~LList() { removeall(); }
//friend istream& operator >> (istream&, T&);
//friend ostream& operator << (ostream&, T&);
void clear() { removeall(); init();}
//Insert at front of right partition
bool insert(const T& item)
{
fence->next = new Link<T>(item, fence->next);
if(tail == fence) tail = fence->next; //New tail
rightcnt++;
return true;
}
//Append Element to end of the list
bool append(const T& item)
{
tail = tail->next = new Link<T>(item, NULL);
rightcnt++;
return true;
}
//Remove and return first element in right partition
bool remove(T& it)
{
if(fence->next == NULL) return false; //Empty right
it = fence->next->element; //Remember value
Link<T>* ltemp = fence->next; //Remember link node
fence->next = ltemp->next; //Remove from list
if(tail == ltemp) tail = fence; //Reset tail
delete ltemp; //Reclaim space
rightcnt--;
return true;
}
void setStart()
{
fence = head; rightcnt += leftcnt; leftcnt = 0;
}
void setEnd()
{
fence = tail; leftcnt += rightcnt; rightcnt = 0;
}
//Move fence ont step left; no change if left is empty
void prev()
{
Link<T>* temp = head;
if(fence == head) return;
while (temp->next!=fence) temp = temp->next;
fence = temp;
leftcnt--; rightcnt++;
}
void next()
{
if(fence != tail) //Don't move fence if right empty
{
fence = fence->next; rightcnt--; leftcnt++;
}
}
int leftLength() const {return leftcnt;}
int rightLength() const {return rightcnt;}
//Set the size of left partition to pos
bool setPos(int pos)
{
if((pos < 0) || (pos > rightcnt+leftcnt)) return false;
fence = head;
for(register int(0); i<pos; i++) fence = fence->next;
return true;
}
bool getValue(T& it) const
{
if(rightLength() == 0) return false;
it = fence->next->element;
return true;
}
void print() const
{
Link<T>* temp = head;
cout<<"< ";
while(temp != fence)
{
cout<<temp->next->element<<" ";
temp = temp->next;
}
cout<<"| ";
while(temp->next != NULL)
{
cout<<temp->next->element<<" ";
temp = temp->next;
}
cout<<">\n";
}
};
}
#endif
