TreeNode * Tree::insert(GenericData * elem, TreeNode *tree) {
if(tree == NULL) {
tree = new TreeNode(elem, NULL, NULL);
}
else {
if(elem->getId() < tree->getElem()->getId()) {
tree->setLeft(insert(elem, tree->getLeft()));
if(height(tree->getLeft()) - height(tree->getRight()) > 1) {
if(elem->getId() < tree->getLeft()->getElem()->getId()) {
tree = singleRotateLeft(tree);
}
else {
tree = doubleRotateLeft(tree);
}
}
}
else if(elem->getId() > tree->getElem()->getId()) {
tree->setRight(insert(elem, tree->getRight()));
if(height(tree->getRight()) - height(tree->getLeft()) > 1) {
if(elem->getId() > tree->getRight()->getElem()->getId()) {
tree = singleRotateRight(tree);
}
else {
tree = doubleRotateRight(tree);
}
}
}
}
return tree;
}
node* doubleRotateRightLeft(node* subtree){
printf("Single right rotate...\n");
subtree->right = singleRotateRight(subtree->right);
printf("Single left rotate...\n");
subtree = singleRotateLeft(subtree);
return subtree;
}
template<class T1, class T2> void DS::map<T1, T2>::_insertAVL(node* current, node* prv, T1 key, T2 value) {
if(current == null){
current = new node();
current->value = value, current->key = key, current->parent = prv, current->leftHeight = current->rightHeight = 0;
if(prv) {
if(prv->key < key) prv->right = current, prv->rightHeight = 1;
else prv->left = current, prv->leftHeight = 1;
} else root = current;
return;
}
_insertAVL(current->key < key ? current->right : current->left, current, key, value);
current->rightHeight = current->right ? _max(current->right) + 1 : 0;
current->leftHeight = current->left ? _max(current->left) + 1 : 0;
int diff = abs(current->rightHeight - current->leftHeight);
node* tmp;
if(diff > 1) { // AVL tree policy is violated - :o - and needs balancing. :D
if(current->rightHeight > current->leftHeight) { // left-rotation
tmp = current->right;
if(tmp->rightHeight > tmp->leftHeight) { // single-rotation
singleRotateLeft(current);
}else { // double-rotation
doubleRotateLeft(current);
}
}else { // right rotation
tmp = current->left;
if(tmp->leftHeight > tmp->rightHeight) { // single-rotation
singleRotateRight(current);
}else { // double-rotation
doubleRotateRight(current);
}
}
}
}
// 查找节点
void find(Tree *tree, int val)
{
Tree *root = tree;
Tree *parentnode = NULL;
Tree *grandnode = NULL;
tree = tree->left;
while (tree) {
if (tree->val == val) {
break;
} else if (tree->val > val) {
tree = tree->left;
} else {
tree = tree->right;
}
}
if (tree && tree->val == val) {
parentnode = tree->parent;
while (parentnode->val != INT_MIN) {
grandnode = parentnode->parent;
if (grandnode->val == INT_MIN) {
if (parentnode->left == tree) {
singleRotateLeft(parentnode);
} else {
singleRotateRight(parentnode);
}
return;
} else {
if (grandnode->left == parentnode && parentnode->left == tree) {
singleRotateLeft(grandnode);
singleRotateLeft(parentnode);
} else if (grandnode->left == parentnode && parentnode->right == tree) {
doubleRotateLeft(grandnode);
} else if (grandnode->right == parentnode && parentnode->right == tree) {
singleRotateRight(grandnode);
singleRotateRight(parentnode);
} else if (grandnode->right == parentnode && parentnode->left == tree) {
doubleRotateRight(grandnode);
}
parentnode = tree->parent;
}
}
}
}
// 左-右旋转
Tree *doubleRotateLeft(Tree *tree)
{
tree->left = singleRotateRight(tree->left);
return singleRotateLeft(tree);
}
TreeNode * Tree::doubleRotateLeft(TreeNode* node){
node->setLeft(singleRotateRight(node->getLeft()));
return singleRotateLeft(node);
}