public void add(int n) {
Node node = new Node(n);
Node temp = head;
if (numItems == 0 || node.getNum() < temp.getNum()) {
node.setNext(temp);
temp.setPrev(node);
head = node;
numItems++;
} else {
for (int i = 0; i <= numItems; i++) {
if (node.getNum() == temp.getNum()) {
temp.getPrev().setNext(node);
node.setPrev(temp.getPrev());
node.setNext(temp);
temp.setPrev(node);
numItems++;
break;
} else if (node.getNum() <= temp.getNum() && temp.getNext() == null) {
temp.setNext(node);
node.setPrev(temp);
node.setNext(null);
numItems++;
break;
} else {
temp = temp.getNext();
}
}
}
}
/**
* Moves the iterator one step backwards in the list. When it hits the end it will not move past
* the start of the list.
*
* @return true if the iterator did not hit the start of the list, false otherwise
*/
public boolean moveToPrev() {
boolean result = false;
if (current != null) {
if (current.getPrev() != null) {
current = current.getPrev();
result = true;
}
}
return result;
}
public boolean delete(E d) {
Node<E> n = current;
if (current == null) {
return false;
}
while (n.getNext() != current) {
if (n.getData() == d) {
n.getPrev().setNext(n.getNext());
n.getNext().setPrev(n.getPrev());
return true;
}
n = n.getNext();
}
return false;
}
public void insert(E d) {
Node<E> n = new Node<E>(d);
if (current == null) {
current = n;
} else if (current.getNext() == null) {
n.setPrev(current);
n.setNext(current);
current.setPrev(n);
current.setNext(n);
current = n;
} else {
n.setNext(current);
n.setPrev(
current.getPrev()); // doesnt need to be in condition because if it is null, its null
if (current.getPrev() != null) current.getPrev().setNext(n);
current.setPrev(n);
current = n;
}
}
@Override
public E remove(IPosition<E> p) throws IllegalArgumentException {
Node<E> node = validate(p);
E oldValue = node.getElement();
Node<E> prevNode = node.getPrev();
Node<E> nextNode = node.getNext();
prevNode.setNext(nextNode);
nextNode.setPrev(prevNode);
node.setElement(null);
node.setNext(null);
node.setPrev(null);
size--;
return oldValue;
}
public Item removeLast() {
if (isEmpty()) {
throw new NoSuchElementException();
}
Node removedNode = last;
last = last.getPrev();
if (last != null) {
last.setNext(null);
} else {
first = null;
}
removedNode.setPrev(null);
count--;
return removedNode.getItem();
}
public void remove(int n) {
Node node = new Node(n);
Node temp = head;
if (node.getNum() == temp.getNum()) {
temp.getNext().setPrev(null);
head = temp.getNext();
numItems--;
} else {
for (int i = 0; i < numItems; i++) {
if (node.getNum() == temp.getNum()) {
temp.getPrev().setNext(temp.getNext());
temp.getNext().setPrev(temp.getPrev());
numItems--;
break;
} else if (node.getNum() == temp.getNum() && temp.getNext() == null) {
temp.getPrev().setNext(null);
numItems--;
break;
} else {
temp = temp.getNext();
}
}
}
}
/**
* return a COPY of solution. This should be : [x1,y1,x2,y2,x3,y3...] the coordinates of the
* solution from start to end. Precondition : one of the solveXXX methods has already been called
* (solveBFS OR solveDFS OR solveAStar) (otherwise an empty array is returned) Postcondition: the
* correct solution is in the returned array
*/
public int[] solutionCoordinates() {
MyQueue<Integer> listOfInts = new MyQueue<Integer>();
Node current = placesToGo.next();
while (current != null) {
listOfInts.enqueue(current.getValue()[0]);
listOfInts.enqueue(current.getValue()[1]);
current = current.getPrev();
}
solution = new int[listOfInts.size()];
for (int i = 0; i < solution.length; i++) {
solution[i] = listOfInts.dequeue();
}
return solution;
}
public void back() {
if (current.getPrev() != null) current = current.getPrev();
}
@Override
public IPosition<E> before(IPosition<E> p) throws IllegalArgumentException {
Node<E> node = validate(p);
return node.getPrev();
}
@Override
public IPosition<E> addLast(E e) {
return addBetween(e, trailer.getPrev(), trailer);
}
@Override
public IPosition<E> last() {
return trailer.getPrev();
}
@Override
public IPosition<E> addBefore(IPosition<E> p, E e) throws IllegalArgumentException {
Node<E> node = validate(p);
return addBetween(e, node.getPrev(), node);
}
