//======Helpers=======
private TwoThreeNode deleteRec(int key, TwoThreeNode parent, TwoThreeNode grandparent)
{
TwoThreeNode toReturn = null;
TwoThreeNode cur = null;
TwoThreeNode returned = null;
TwoThreeNode temp = null;
int pstate = -1;
int state = -1;
if (key < parent.getFirstKey())
{
cur = parent.getLeft();
state = 0;
}
else if ((key >= parent.getFirstKey() && parent.hasTwoNodes()) || (parent.hasTwoNodes() == false && key >= parent.getFirstKey() && key < parent.getSecondKey()))
{
cur = parent.getMid();
state = 1;
}
else if (parent.hasTwoNodes() == false && key >= parent.getSecondKey())
{
cur = parent.getRight();
state = 2;
}
if (cur.isLeafNode() && cur.getFirstKey() == key)
{
if (parent.hasTwoNodes() == false)
{
//Parent is a three node, toggle the Node numbers, delete the key node, shift children as necessary and change key as necessary
parent.toggleNodeNum();
if (state == 0)
{
parent.setLeft(parent.getMid());
parent.setMid(parent.getRight());
parent.setRight(null);
parent.setFirstKey(parent.getSecondKey());
}
else if (state == 1)
{
parent.setMid(parent.getRight());
parent.setRight(null);
parent.setFirstKey(parent.getSecondKey());
}
else if (state == 2)
{
parent.setRight(null);
}
}
else
{
if (grandparent == null)
{
//Parent node is the root
if (state == 0)
{
root = parent.getMid();
}
else if (state == 1)
{
root = parent.getLeft();
}
}else if(grandparent.hasTwoNodes() == false){
if (state == 0)
{
temp = parent.getMid();
}
else if(state == 1)
{
temp = parent.getLeft();
}
//Grandparent node is a three node
if (parent == grandparent.getLeft())
{
if (grandparent.getMid().hasTwoNodes())
{
//Closest sibling of parent is a two node, so merge other child of parent with parent's sibling and remove parent then change key as necessary
grandparent.getMid().toggleNodeNum();
grandparent.getMid().setRight(grandparent.getMid().getMid());
grandparent.getMid().setMid(grandparent.getMid().getLeft());
grandparent.getMid().setLeft(temp);
grandparent.getMid().setSecondKey(grandparent.getMid().getFirstKey());
grandparent.getMid().setFirstKey(grandparent.getMid().getMid().getFirstKey());
grandparent.toggleNodeNum();
grandparent.setLeft(grandparent.getMid());
grandparent.setMid(grandparent.getRight());
grandparent.setFirstKey(grandparent.getSecondKey());
}
else
{
//Closest sibling of parent has three nodes, so take the left most node of the sibling and attach it to the parent, fix sibling push key up to grandparent node
parent.setLeft(temp);
parent.setMid(grandparent.getMid().getLeft());
parent.setFirstKey(parent.getMid().getFirstKey());
grandparent.getMid().toggleNodeNum();
grandparent.getMid().setLeft(grandparent.getMid().getMid());
grandparent.getMid().setMid(grandparent.getMid().getRight());
grandparent.getMid().setFirstKey(grandparent.getSecondKey());
}
}
else if (parent == grandparent.getMid())
{
if (grandparent.getLeft().hasTwoNodes())
{
//The left sibling of the parents has two nodes, so take the one node left in the middle after deleting a merge it with the parent's left sibling, adjust grandparent node as necessary
grandparent.getLeft().toggleNodeNum();
grandparent.getLeft().setRight(temp);
grandparent.getLeft().setSecondKey(temp.getFirstKey());
grandparent.toggleNodeNum();
grandparent.setMid(grandparent.getRight());
grandparent.setFirstKey(minKeyInTree(grandparent.getMid()));
grandparent.setRight(null);
}
else
{
//The left sibling of the parent has three nodes, so take its right most node and bring it into the center, adjust left sibling as necessary and adjust grandparent as necessary
if (state == 0)
{
parent.setLeft(grandparent.getLeft().getRight());
}
else
{
parent.setMid(temp);
parent.setFirstKey(temp.getFirstKey());
parent.setLeft(grandparent.getLeft().getRight());
}
grandparent.setFirstKey(grandparent.getLeft().getRight().getFirstKey());
grandparent.getLeft().toggleNodeNum();
grandparent.getLeft().setRight(null);
}
}
else if (parent == grandparent.getRight())
{
if (grandparent.getMid().hasTwoNodes())
{
//The parents middle sibling has two nodes, so merge the remaining node with the parent's middle sibling, and adjust the grandparent as necessary
grandparent.getMid().setRight(temp);
grandparent.getMid().toggleNodeNum();
grandparent.getMid().setSecondKey(temp.getFirstKey());
grandparent.setRight(null);
grandparent.toggleNodeNum();
}
else
{
//The parents middle sibling has three nodes, so take the middle siblings right most node and add it to the parent node
if (state == 0)
{
parent.setLeft(grandparent.getMid().getRight());
}
else if (state == 1)
{
parent.setRight(temp);
parent.setLeft(grandparent.getMid().getRight());
parent.setFirstKey(temp.getFirstKey());
}
grandparent.setSecondKey(grandparent.getMid().getRight().getFirstKey());
grandparent.getMid().toggleNodeNum();
grandparent.getMid().setRight(null);
}
}
}
else if (grandparent.hasTwoNodes())
{
if (cur == parent.getLeft())
{
state = 0;
temp = parent.getMid();
}
else if (cur == parent.getMid())
{
state = 1;
temp = parent.getLeft();
}
if (parent == grandparent.getLeft())
{
if (grandparent.getMid().hasTwoNodes() == false)
{
//The parent's sibling has three nodes, so take one node from the sibling and merge it with the parent node
if (state == 0)
{
parent.setLeft(parent.getMid());
parent.setMid(grandparent.getMid().getLeft());
parent.setFirstKey(parent.getMid().getFirstKey());
grandparent.getMid().setLeft(grandparent.getMid().getMid());
grandparent.getMid().setMid(grandparent.getMid().getRight());
grandparent.getMid().toggleNodeNum();
grandparent.getMid().setFirstKey(grandparent.getMid().getSecondKey());
}
else if (state == 1)
{
parent.setMid(grandparent.getMid().getLeft());
parent.setFirstKey(parent.getMid().getFirstKey());
grandparent.getMid().setLeft(grandparent.getMid().getMid());
grandparent.getMid().setMid(grandparent.getMid().getRight());
grandparent.getMid().toggleNodeNum();
grandparent.getMid().setFirstKey(grandparent.getMid().getSecondKey());
}
}
else
{
//The parent's sibling has two nodes, so merge all leafs into a three node, and push it up the tree
grandparent.getMid().toggleNodeNum();
grandparent.getMid().setRight(grandparent.getMid().getMid());
grandparent.getMid().setMid(grandparent.getMid().getLeft());
grandparent.getMid().setLeft(temp);
grandparent.getMid().setSecondKey(grandparent.getMid().getFirstKey());
grandparent.getMid().setFirstKey(grandparent.getMid().getMid().getFirstKey());
toReturn = grandparent.getMid();
}
}
else if (parent == grandparent.getMid())
{
if (grandparent.getLeft().hasTwoNodes() == false)
{
if (state == 0)
{
parent.setLeft(grandparent.getLeft().getRight());
grandparent.getLeft().toggleNodeNum();
grandparent.getLeft().setRight(null);
}
else if (state == 1)
{
parent.setMid(temp);
parent.setLeft(grandparent.getLeft().getRight());
grandparent.getLeft().toggleNodeNum();
grandparent.getLeft().setRight(null);
}
}
else
{
grandparent.getLeft().toggleNodeNum();
grandparent.getLeft().setRight(temp);
grandparent.getLeft().setSecondKey(temp.getFirstKey());
toReturn = grandparent.getLeft();
}
}
}
}
}
else
{
returned = deleteRec(key, cur, parent);
if (returned != null)
{
if(grandparent == null){
//Pushed up to the root Node
root = returned;
}
else if (grandparent.hasTwoNodes())
{
if (parent == grandparent.getLeft())
{
state = 0;
}
else if (parent == grandparent.getMid())
{
state = 1;
}
else if (parent == grandparent.getRight())
{
state = 2;
}
if (state == 0 && grandparent.getMid().hasTwoNodes() == false)
{
//The left node has been pushed up, the grand parent is a two nodes, the grandparents middle node is three node, so take the left subtree of the middle node merge it with the pushed up node,
//then set the middle node's keys and grandparent's key as necessary
temp = new TwoThreeNode(returned, grandparent.getMid().getLeft(), minKeyInTree(grandparent.getMid().getLeft()));
grandparent.setLeft(temp);
grandparent.getMid().toggleNodeNum();
grandparent.getMid().setLeft(grandparent.getMid().getMid());
grandparent.getMid().setMid(grandparent.getMid().getRight());
grandparent.getMid().setFirstKey(grandparent.getMid().getSecondKey());
grandparent.getMid().setRight(null);
grandparent.setFirstKey(minKeyInTree(grandparent.getMid()));
}
else if (state == 0 && grandparent.getMid().hasTwoNodes())
{
//The left node has been pushed up, the grand parent is a two node, the grand parents middle node is a two node, so merge grandparents children into a single node and push it up
grandparent.getMid().toggleNodeNum();
grandparent.getMid().setRight(grandparent.getMid().getMid());
grandparent.getMid().setMid(grandparent.getMid().getLeft());
grandparent.getMid().setLeft(returned);
grandparent.getMid().setSecondKey(grandparent.getMid().getFirstKey());
grandparent.getMid().setFirstKey(minKeyInTree(grandparent.getMid().getMid()));
toReturn = grandparent.getMid();
}
else if (state == 1 && grandparent.getLeft().hasTwoNodes() == false)
{
temp = new TwoThreeNode(grandparent.getMid().getRight(), returned, minKeyInTree(returned));
grandparent.setMid(temp);
grandparent.getLeft().toggleNodeNum();
grandparent.getLeft().setRight(null);
}
else if (state == 1 && grandparent.getLeft().hasTwoNodes())
{
grandparent.getLeft().toggleNodeNum();
grandparent.getLeft().setRight(returned);
grandparent.getLeft().setSecondKey(minKeyInTree(returned));
toReturn = grandparent.getLeft();
}
}
else
{
if (state == 0 && grandparent.getMid().hasTwoNodes() == false)
{
temp = new TwoThreeNode(new TwoThreeNode(returned.getLeft(), returned.getMid(), minKeyInTree(returned.getLeft())), new TwoThreeNode(returned.getRight(), grandparent.getMid().getLeft(),
minKeyInTree(grandparent.getMid().getLeft())), minKeyInTree(returned.getRight()));
grandparent.setLeft(temp);
grandparent.getMid().toggleNodeNum();
grandparent.getMid().setLeft(grandparent.getMid().getMid());
grandparent.getMid().setMid(grandparent.getMid().getRight());
grandparent.getMid().setFirstKey(grandparent.getMid().getFirstKey());
}else if(state == 0 && grandparent.getMid().hasTwoNodes()){
grandparent.getMid().toggleNodeNum();
grandparent.getMid().setRight(grandparent.getMid().getMid());
grandparent.getMid().setMid(grandparent.getMid().getLeft());
grandparent.getMid().setLeft(returned);
grandparent.getMid().setSecondKey(grandparent.getMid().getFirstKey());
grandparent.getMid().setFirstKey(minKeyInTree(grandparent.getMid().getMid()));
grandparent.setLeft(grandparent.getMid());
grandparent.setMid(grandparent.getRight());
grandparent.toggleNodeNum();
grandparent.setFirstKey(grandparent.getSecondKey());
}
else if (state == 1 && grandparent.getLeft().hasTwoNodes()==false)
{
//State when all three children of the grandparent are two nodes
temp = new TwoThreeNode(new TwoThreeNode(grandparent.getLeft().getRight(), returned.getLeft(), minKeyInTree(grandparent.getLeft().getRight())), new TwoThreeNode(returned.getMid(),
returned.getRight(), minKeyInTree(returned.getRight())), minKeyInTree(returned.getMid()));
grandparent.setMid(temp);
grandparent.setFirstKey(minKeyInTree(temp));
grandparent.getLeft().toggleNodeNum();
grandparent.getLeft().setRight(null);
}else if(state == 1 && grandparent.getLeft().hasTwoNodes()){
grandparent.getLeft().toggleNodeNum();
grandparent.getLeft().setRight(returned);
grandparent.getLeft().setSecondKey(minKeyInTree(returned));
grandparent.setMid(grandparent.getRight());
grandparent.toggleNodeNum();
grandparent.setFirstKey(grandparent.getSecondKey());
grandparent.setRight(null);
}
else if (state == 2 && grandparent.getMid().hasTwoNodes() == false)
{
temp = new TwoThreeNode(new TwoThreeNode(grandparent.getMid().getRight(), returned.getLeft(), minKeyInTree(returned.getLeft())), new TwoThreeNode(returned.getMid(), returned.getRight(),
minKeyInTree(returned.getRight())), minKeyInTree(returned.getMid()));
grandparent.setRight(temp);
grandparent.setSecondKey(minKeyInTree(temp));
}
else if (state == 2 && grandparent.getMid().hasTwoNodes())
{
grandparent.getMid().toggleNodeNum();
grandparent.getMid().setRight(returned);
grandparent.setSecondKey(minKeyInTree(returned));
grandparent.setRight(null);
grandparent.toggleNodeNum();
}
}
}
}
return toReturn;
}
private TwoThreeNode addRec(TwoThreeNode curNode, int key)
{
TwoThreeNode toReturn = null;
TwoThreeNode returned = null;
TwoThreeNode newLeft = null;
TwoThreeNode newRight = null;
TwoThreeNode newParent = null;
if(!curNode.isLeafNode()){
//A key has been pushed up, which needs to be added to the curNode node
if (curNode.hasTwoNodes() == true)
{
if(key < curNode.getFirstKey()){
returned = addRec(curNode.getLeft(), key);
}else{
returned = addRec(curNode.getMid(), key);
}
if(returned != null){
if (returned.getFirstKey() < curNode.getFirstKey())
{
curNode.toggleNodeNum();
curNode.setRight(curNode.getMid());
curNode.setMid(returned.getMid());
curNode.setLeft(returned.getLeft());
curNode.setSecondKey(curNode.getFirstKey());
curNode.setFirstKey(minKeyInTree(curNode.getMid()));
}else if(returned.getFirstKey() >= curNode.getFirstKey()){
curNode.toggleNodeNum();
curNode.setRight(returned.getMid());
curNode.setMid(returned.getLeft());
curNode.setFirstKey(minKeyInTree(returned.getLeft()));
curNode.setSecondKey(minKeyInTree(returned.getMid()));
}
}
}
else
{
if(key < curNode.getFirstKey()){
returned = addRec(curNode.getLeft(), key);
}else if(key < curNode.getSecondKey()){
returned = addRec(curNode.getMid(), key);
}else{
returned = addRec(curNode.getRight(), key);
}
if(returned != null){
if (returned.getFirstKey() < curNode.getFirstKey())
{
newLeft = new TwoThreeNode(returned.getLeft(), returned.getMid(), minKeyInTree(returned.getMid()));
newRight = new TwoThreeNode(curNode.getMid(), curNode.getRight(), minKeyInTree(curNode.getRight()));
}
else if (returned.getFirstKey() >= curNode.getFirstKey() && returned.getFirstKey() < curNode.getSecondKey())
{
newLeft = new TwoThreeNode(curNode.getLeft(), returned.getLeft(), minKeyInTree(returned.getLeft()));
newRight = new TwoThreeNode(returned.getMid(), curNode.getRight(), minKeyInTree(curNode.getRight()));
}else{
if (returned.getFirstKey() >= curNode.getSecondKey())
{
newLeft = new TwoThreeNode(curNode.getLeft(), curNode.getMid(), minKeyInTree(curNode.getMid()));
newRight = new TwoThreeNode(returned.getLeft(), returned.getMid(), minKeyInTree(returned.getMid()));
}
else
{
newLeft = new TwoThreeNode(curNode.getLeft(), curNode.getMid(), minKeyInTree(curNode.getMid()));
newRight = new TwoThreeNode(returned.getLeft(), returned.getMid(), minKeyInTree(returned.getMid()));
}
}
newParent = new TwoThreeNode(newLeft, newRight, minKeyInTree(newRight));
toReturn = newParent;
}
}
}else{
//Base Case: Return a the parent node consisting of two child nodes, the leaf node
if(key < curNode.getFirstKey()){
toReturn = new TwoThreeNode(new TwoThreeNode(key), curNode, curNode.getFirstKey());
}else if(key > curNode.getFirstKey()){
toReturn = new TwoThreeNode(curNode, new TwoThreeNode(key), key);
}
}
return toReturn;
}