avlTreeNode* balanceLeft(avlTreeNode* root)
{
int balanceDifference;
balanceDifference = calculateMaxHight( root-> leftTree );
printf("\nIn balanceLeft Insertion\n");
switch ( balanceDifference )
{
case 1: case 0:
{
printf("\nIn RightRotation Insertion\n");
return rightRotation( root );
}
case -1:
{
printf("\nIn LeftRotation Insertion\n");
root -> leftTree = leftRotation( root -> leftTree );
printf("\nIn RightRotation Insertion\n");
return rightRotation( root );
}
}
return root;
}
NodeT *Balance(NodeT *root)
{
int balance = getBalance(root);
if(balance == -2)
{
balance = getBalance(root->left);
if(balance >=1)
{
root -> left = leftRotation(root->left);
root = rightRotation(root);
}
else
root = rightRotation(root);
}
else
{
if(balance == 2)
{
balance = getBalance(root);
if(balance <= -1)
{
root -> right = rightRotation(root->right);
root = leftRotation(root);
}
else
root = leftRotation(root);
}
}
getHeights(root);
return root;
}
// Worst case insertion O(2*logn)
struct Node *insert(struct Node *root,int data)
{
if(root == NULL)
return create(data);
if(data > root->data)
root->right = insert(root->right,data);
else
root->left = insert(root->left,data);
root->height = max(height(root->left),height(root->right)) + 1;
int balance = getbalance(root);
// left left case
if(balance > 1 && data < root->left->data)
return rightRotation(root);
else // left right case
if(balance > 1 && data > root->left->data)
{
root->left = leftRotation(root->left);
return rightRotation(root);
}
else // right-right case
if(balance < -1 && data > root->right->data)
{
return leftRotation(root);
}
else // right left case;
if(balance < -1 && data < root->right->data)
{
root->right = rightRotation(root->right);
return leftRotation(root);
}
// no change required;
return root;
}
avlTreeNode* balanceRight( avlTreeNode* root )
{
int balanceDifference;
printf("\nIn BalnaceRight Insertion\n");
balanceDifference = calculateMaxHight( root-> rightTree );
printf("========== %d\n",balanceDifference);
switch ( balanceDifference )
{
case 1:
{
printf("\nIn RightRotation Insertion\n");
root -> rightTree = rightRotation( root -> rightTree );
printf("\nIn leftRotation Insertion\n");
return leftRotation( root );
}
case -1: case 0 :
{
return leftRotation( root );
}
}
return root;
}
NodeT* insertNodeAVLtree(NodeT* root, int data)
{
if(root==NULL)
return createNodeT(data);
else
{
if(root->data < data)
root->right=insertNodeAVLtree(root->right, data);
else
root->left=insertNodeAVLtree(root->left, data);
}
root->height=maxx(height(root->left), height(root->right))+1;
int aux=balanceFactor(root);
if(aux>1)
{
if(root->left->data > data)//RR
rightRotation(&root);
else//LR
LeftRight(&root);
}
else if(aux<-1)
{
if(root->right->data < data)//LL
leftRotation(&root);
else//RL
RightLeft(&root);
}
//else
return root;
}
TREE* insert(char * name, TREE * t){
addNum++;
if(t == NULL){
t = (TREE*)malloc(sizeof(TREE));
t -> name = name;
t -> height = 0;
t -> ls = t -> rs = NULL;
return t;
}
else if(strcmp(name, t -> name) <= 0){
t -> ls = insert(name, t -> ls);
if(height(t -> ls) - height(t -> rs) == 2 ){
if(strcmp(name, t -> ls -> name) <= 0)
t = leftRotation(t);
else
t = doubleLeftRotation(t);
}
}
else if(strcmp(name, t -> name) > 0){
t -> rs = insert(name, t -> rs);
if(height(t -> rs) - height(t -> ls) == 2){
if(strcmp(name, t -> rs -> name) > 0)
t = rightRotation(t);
else
t = doubleRightRotation(t);
}
}
t->height = MAX(height(t -> ls), height(t -> rs)) + 1;
return t;
}
nodePtr splay(char* word, nodePtr leaf)
{
if(leaf->left != NULL && strcmp(leaf->left->info.word, word)==0)
return rightRotation(leaf);
else if (leaf->right != NULL && strcmp(leaf->right->info.word, word)==0)
return leftRotation(leaf);
return leaf;
}
void BinarySearchTree::twoRotations(Node *TopNode, Node *SubNode, bool direction) {
if(direction == LINKED_LEFT) {
// If top node was linked left then rotate to the right
// and link to balanced tree
TopNode->assignNewRightNode(rightRotation(SubNode));
rotateAndLink(TopNode, LINKED_LEFT);
} else {
TopNode->assignNewLeftNode(leftRotation(SubNode));
rotateAndLink(TopNode, LINKED_RIGHT);
}
}
void BinarySearchTree::rotateAndLink(Node* TopNode, bool direction) {
// Link the balanced subtree back to the Binary Search Tree
if(direction == LINKED_LEFT) {
if(TopNode == RootNode)
RootNode = leftRotation(TopNode);
else {
Node *TreeNodeLink = TopNode->getHigherNodePtr();
if(TopNode->getHigherNodeDir() == LINKED_LEFT)
TreeNodeLink->assignNewLeftNode(leftRotation(TopNode));
else
TreeNodeLink->assignNewRightNode(leftRotation(TopNode));
}
} else {
if(TopNode == RootNode)
RootNode = rightRotation(TopNode);
else {
Node *TreeNodeLink = TopNode->getHigherNodePtr();
if(TopNode->getHigherNodeDir() == LINKED_LEFT)
TreeNodeLink->assignNewLeftNode(rightRotation(TopNode));
else
TreeNodeLink->assignNewRightNode(rightRotation(TopNode));
}
}
}
nodePtr rootInsertion(char* word, nodePtr leaf)
{
if(leaf == NULL)
return createNode(word);
if(strcmp(word,leaf->info.word ) < 0)
{
leaf->left = rootInsertion(word, leaf->left);
leaf = rightRotation(leaf);
}
else if((strcmp(word,leaf->info.word) > 0))
{
leaf->right = rootInsertion(word,leaf->right);
leaf = leftRotation(leaf);
}
return leaf;
}
void avlInsert(treePointer *parent, element x, int *unbalanced)
{
if (!*parent) {
*unbalanced = TRUE;
*parent = malloc(sizeof(Node));
(*parent)->leftChild = (*parent)->rightChild = NULL;
(*parent)->bf = 0;
(*parent)->data = x;
} else if (x.key < (*parent)->data.key) {
avlInsert(&(*parent)->leftChild, x, unbalanced);
if (*unbalanced)
switch ((*parent)->bf) {
case -1:
(*parent)->bf = 0;
*unbalanced = FALSE;
break;
case 0:
(*parent)->bf = 1;
break;
case 1:
leftRotation(parent, unbalanced);
}
} else if (x.key > (*parent)->data.key) {
avlInsert(&((*parent)->rightChild), x, unbalanced);
if (*unbalanced)
switch ((*parent)->bf) {
case 1:
(*parent)->bf = 0;
*unbalanced = FALSE;
break;
case 0:
(*parent)->bf = -1;
break;
case -1:
rightRotation(parent, unbalanced);
}
} else {
*unbalanced = FALSE;
printf("The key is already in the tree");
}
}
Tree* checkBalance(Tree *t) {
int h;
if(t->left != NULL && t->right != NULL)
h = height(t);
if(height(t->left) - height(t->right) > 1) {
if (height(t->left->left) - height(t->left->right) > 0)
t = rightRotation(t);
else
t = leftAndRightRotation(t);
}
else
if(height(t->left) - height(t->right) < -1) {
if (height(t->right->left) - height(t->right->right) < 0)
t = leftRotation(t);
else
t = rightAndLeftRotation(t);
}
return t;
}
void avlInsert(treePointer *parent,element x,int *unbalanced)
{
void leftRotation(treePointer *parent,int *unbalanced);
void rightRotation(treePointer *parent,int *unbalanced);
if(!*parent) { // insert element into null tree
*unbalanced=TRUE;
MALLOC(*parent,sizeof(treePointer));
(*parent)->leftChild=(*parent)->rightChild=NULL;
(*parent)->bf=0;
(*parent)->data=x;
}
else if(x.key<(*parent)->data.key) {
avlInsert(&(*parent)->leftChild,x,unbalanced);
if(*unbalanced)
// left branch has grown higher
switch((*parent)->bf) {
case -1: (*parent)->bf=0;
*unbalanced=FALSE; break;
case 0: (*parent)->bf=1; break;
case 1: leftRotation(parent,unbalanced);
}
}
else if(x.key>(*parent)->data.key) {
avlInsert(&(*parent)->rightChild,x,unbalanced);
if(*unbalanced)
// right branch has grown higher
switch((*parent)->bf) {
case 1: (*parent)->bf=0;
*unbalanced=FALSE; break;
case 0: (*parent)->bf=-1; break;
case -1: rightRotation(parent,unbalanced);
}
}
else {
*unbalanced=FALSE;
printf("The key is already in the tree\n");
}
}
void rightLeftRotation(NodeT **root3)
{
rightRotation(&((*root3)->right));
leftRotation(root3);
}
void leftRightRotation(NodeT **root3)
{
leftRotation(&((*root3)->left));
rightRotation(root3);
}
void RightLeft(NodeT** root)
{
rightRotation(& ((*root)->right));
leftRotation(root);
}
void LeftRight(NodeT** root)
{
leftRotation(& ((*root)->left));
rightRotation(root);
}
TREE* doubleRightRotation(TREE * k1){
k1 -> rs = leftRotation(k1 -> rs);
return rightRotation(k1);
}
Tree* rightAndLeftRotation(Tree *t) {
t = rightRotation(t);
return leftRotation(t);
}
Tree* leftAndRightRotation(Tree *t) {
t = leftRotation(t);
return rightRotation(t);
}
TREE* doubleLeftRotation(TREE * k3){
k3 -> ls = rightRotation(k3 -> ls);
return leftRotation(k3);
}