/**
* Inserts a node into the SplayTree, then splays around that node.
*
* @param comp Comparable value of new node being added
*/
public void insert(Comparable comp) {
Node node = new Node(comp);
if (rootNode == null && size == 0) {
rootNode = node;
return;
}
splay(comp);
int temp = comp.compareTo(rootNode.getValue());
if (temp == 0) // Double checks for duplicates
return;
if (temp < 0) {
node.setLeft(rootNode.getLeft());
node.setRight(rootNode);
rootNode.setLeft(null);
} else {
node.setRight(rootNode.getRight());
node.setLeft(rootNode);
rootNode.setRight(null);
}
rootNode = node;
size++;
}
private Node rotateLeft(Node localRoot) {
System.out.println("Rotating Left");
Node temp = localRoot.getRight();
localRoot.setRight(temp.getLeft());
temp.setLeft(localRoot);
//// hint this was only three lines that I took out.
return temp;
}
private Node rotateRight(Node localRoot) { // make sure this and rotate left is correct
System.out.println("Rotating Right");
Node temp = localRoot.getLeft();
localRoot.setLeft(temp.getRight());
temp.setRight(localRoot);
// There is where you set up your references to get the proper rotation
// see hint in rotateLeft
return temp;
}
/**
* Makes the Node node the rootNode of the SplayTree.
*
* @param node Node to be splayed
*/
public void splay(Comparable comp) {
Node left = head;
Node right = head;
Node top = rootNode;
Node temp;
head.setLeft(null);
head.setRight(null);
while (true) {
if (comp.compareTo(top.getValue()) < 0) {
if (top.getLeft() == null) // exit
break;
if (comp.compareTo(top.getLeft().getValue()) < 0) { // Rotate right
temp = top.getLeft();
top.setLeft(temp.getRight());
temp.setRight(top);
top = temp;
if (top.getLeft() == null) // exit
break;
}
right.setLeft(top); // Links the right
right = top;
top = top.getLeft();
} else if (comp.compareTo(top.getValue()) > 0) {
if (top.getRight() == null) // exit
break;
if (comp.compareTo(top.getRight().getValue()) > 0) { // Rotate left
temp = top.getRight();
top.setRight(temp.getLeft());
temp.setLeft(top);
top = temp;
if (top.getRight() == null) // exit
break;
}
left.setRight(top); // Links the left
left = top;
top = top.getRight();
} else break; // exit
}
left.setRight(top.getLeft());
right.setLeft(top.getRight());
top.setLeft(head.getRight());
top.setRight(head.getLeft());
rootNode = top;
}
private Node add(Node localRoot, int item) {
if (localRoot == null) {
addReturn = true;
increase = true;
System.out.println("Added " + item);
return new Node(item);
}
System.out.println("Add called with " + localRoot.getItem() + " as the root.");
if (item == localRoot.getItem()) { // item is alreday in tree
increase = false;
addReturn = false;
return localRoot;
} else if (item < localRoot.getItem()) {
System.out.println("Branching left"); // item < data
localRoot.setLeft(add(localRoot.getLeft(), item));
if (increase) {
decrementBalance(localRoot);
if (localRoot.balance < Node.LEFT_HEAVY) {
increase = false;
return rebalanceLeft(localRoot);
}
}
return localRoot; // Rebalance not needed.
} else {
System.out.println("Branching right"); // item > data
localRoot.setRight(add(localRoot.getRight(), item));
if (increase) {
incrementBalance(localRoot);
if (localRoot.balance > Node.RIGHT_HEAVY) {
return rebalanceRight(localRoot);
} else {
return localRoot;
}
} else {
return localRoot;
}
}
}