Objective: Manipulate the Linked List Pointer. Make acopy of LList.java and rename it to LListr.java. Add a reverse function in LListr.java to reverse the order of the linked list. You can either use the gamescore.txt to test the reverse function. Llist.Java File: /** Source code example for \"A Practical Introduction to Data Structures and Algorithm Analysis, 3rd Edition (Java)\" by Clifford A. Shaffer Copyright 2008-2011 by Clifford A. Shaffer */ // Doubly linked list implementation class LList implements List { private DLink head; // Pointer to list header private DLink tail; // Pointer to last element in list protected DLink curr; // Pointer ahead of current element int cnt; // Size of list //Constructors LList(int size) { this(); } // Ignore size LList() { curr = head = new DLink(null, null); // Create header node tail = new DLink(head, null); head.setNext(tail); cnt = 0; } public void clear() { // Remove all elements from list head.setNext(null); // Drop access to rest of links curr = head = new DLink(null, null); // Create header node tail = new DLink(head, null); head.setNext(tail); cnt = 0; } public void moveToStart() // Set curr at list start { curr = head; } public void moveToEnd() // Set curr at list end { curr = tail.prev(); } /** Insert \"it\" at current position */ public void insert(E it) { curr.setNext(new DLink(it, curr, curr.next())); curr.next().next().setPrev(curr.next()); cnt++; } /** Append \"it\" to list */ public void append(E it) { tail.setPrev(new DLink(it, tail.prev(), tail)); tail.prev().prev().setNext(tail.prev()); cnt++; } /** Remove and return current element */ public E remove() { if (curr.next() == tail) return null; // Nothing to remove E it = curr.next().element(); // Remember value curr.next().next().setPrev(curr); curr.setNext(curr.next().next()); // Remove from list cnt--; // Decrement the count return it; // Return value removed } /** Move curr one step left; no change if at front */ public void prev() { if (curr != head) // Can\'t back up from list head curr = curr.prev(); } // Move curr one step right; no change if at end public void next() { if (curr != tail.prev()) curr = curr.next(); } public int length() { return cnt; } // Return the position of the current element public int currPos() { DLink temp = head; int i; for (i=0; curr != temp; i++) temp = temp.next(); return i; } // Move down list to \"pos\" position public void moveToPos(int pos) { assert (pos>=0) && (pos<=cnt) : \"Position out of range\"; curr = head; for(int i=0; i. The vertical * bar represents the current location of the fence. This method * uses toString() on the individual elements. * @return The string representation of this list */ public String toString() { // Save the current position of the list int oldPos = currPos(); int length = length(); StringBuffer out = new StringBuffer((length() + 1) * 4); moveToStart(); out.append(\"< \"); for (int i = 0; i < oldPos; i++) { if (getValue()!=null) { out.append(getValue()); out.append(\.

1. Objective: Manipulate the Linked List Pointer.
Make acopy of LList.java and rename it to LListr.java. Add a reverse function in LListr.java to
reverse the order of the linked list.
You can either use the gamescore.txt to test the reverse function.
Llist.Java File:
/** Source code example for "A Practical Introduction to Data
Structures and Algorithm Analysis, 3rd Edition (Java)"
by Clifford A. Shaffer
Copyright 2008-2011 by Clifford A. Shaffer
*/
// Doubly linked list implementation
class LList implements List {
private DLink head; // Pointer to list header
private DLink tail; // Pointer to last element in list
protected DLink curr; // Pointer ahead of current element
int cnt; // Size of list
//Constructors
LList(int size) { this(); } // Ignore size
LList() {
curr = head = new DLink(null, null); // Create header node
tail = new DLink(head, null);
head.setNext(tail);
cnt = 0;
}
public void clear() { // Remove all elements from list
head.setNext(null); // Drop access to rest of links
curr = head = new DLink(null, null); // Create header node
tail = new DLink(head, null);
head.setNext(tail);
cnt = 0;
}
public void moveToStart() // Set curr at list start
{ curr = head; }
public void moveToEnd() // Set curr at list end
{ curr = tail.prev(); }

2. /** Insert "it" at current position */
public void insert(E it) {
curr.setNext(new DLink(it, curr, curr.next()));
curr.next().next().setPrev(curr.next());
cnt++;
}
/** Append "it" to list */
public void append(E it) {
tail.setPrev(new DLink(it, tail.prev(), tail));
tail.prev().prev().setNext(tail.prev());
cnt++;
}
/** Remove and return current element */
public E remove() {
if (curr.next() == tail) return null; // Nothing to remove
E it = curr.next().element(); // Remember value
curr.next().next().setPrev(curr);
curr.setNext(curr.next().next()); // Remove from list
cnt--; // Decrement the count
return it; // Return value removed
}
/** Move curr one step left; no change if at front */
public void prev() {
if (curr != head) // Can't back up from list head
curr = curr.prev();
}
// Move curr one step right; no change if at end
public void next()
{ if (curr != tail.prev()) curr = curr.next(); }
public int length() { return cnt; }
// Return the position of the current element
public int currPos() {
DLink temp = head;
int i;
for (i=0; curr != temp; i++)
temp = temp.next();

3. return i;
}
// Move down list to "pos" position
public void moveToPos(int pos) {
assert (pos>=0) && (pos<=cnt) : "Position out of range";
curr = head;
for(int i=0; i. The vertical
* bar represents the current location of the fence. This method
* uses toString() on the individual elements.
* @return The string representation of this list
*/
public String toString()
{
// Save the current position of the list
int oldPos = currPos();
int length = length();
StringBuffer out = new StringBuffer((length() + 1) * 4);
moveToStart();
out.append("< ");
for (int i = 0; i < oldPos; i++) {
if (getValue()!=null)
{
out.append(getValue());
out.append(" ");
}
next();
}
out.append("| ");
for (int i = oldPos; i < length; i++) {
out.append(getValue());
out.append(" ");
next();
}
out.append(">");
moveToPos(oldPos); // Reset the fence to its original position
return out.toString();

4. }
}
gamescore.txt
Mike,1105
Rob,750
Paul,720
Anna,660
Rose,590
Jack,510
gamescore.txt
Solution
Here is the function you need:
public void reverseList()
{
DLink oldStart = tail; //Copies the last node address.
DLink temp; //Holds a temporary pointer to hold a node.
moveToStart(); //Makes the current move to the first position.
while(oldStart != head)
{
temp = remove(); //Removes the first element in the list.
append(temp); //Appends it to the end of the list.
moveToStart(); //Makes the current move to the first position.
}
}