Middle
What tree balancing algorithms are you familiar with?
sobes.tech AI
Answer from AI
There are several main algorithms for tree balancing:
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Rotation-based algorithms: These algorithms maintain balance by performing rotation operations during node insertion or deletion.
- AVL trees: Maintain the condition that for each node, the difference in height between the left and right subtrees does not exceed 1.
struct Node { int key; Node *left, *right; int height; }; // Function to get the height of a node int height(Node *N) { if (N == NULL) return 0; return N->height; } // Function to compute the balance factor of a node int getBalance(Node *N) { if (N == NULL) return 0; return height(N->left) - height(N->right); } // Right rotation Node *rightRotate(Node *y) { Node *x = y->left; Node *T2 = x->right; x->right = y; y->left = T2; y->height = 1 + max(height(y->left), height(y->right)); x->height = 1 + max(height(x->left), height(x->right)); return x; }- Red-Black trees: Maintain balance by assigning colors (red or black) to nodes and following a set of rules.
enum Color { RED, BLACK }; struct Node { int key; Node *left, *right, *parent; Color color; }; // Function to insert a node and balance Node* insert(Node* root, Node* pt) { // Standard BST insertion if (root == NULL) return pt; if (pt->key < root->key) { root->left = insert(root->left, pt); root->left->parent = root; } else if (pt->key > root->key) { root->right = insert(root->right, pt); root->right->parent = root; } return root; // TODO: Implement balancing } -
Treaps: Combine properties of binary search trees and heaps. Each node has a key and a priority. They are structured so that they are a search tree by keys and a heap by priorities.
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B-trees and their variants (B-trees, B+-trees, B-trees):* Often used for external storage data (disks) to minimize I/O operations. Each node can have multiple children.
Algorithm Properties Application AVL trees Strictly balanced by height. Fast search operations. In-memory search. Red-Black trees Not strictly height-balanced, but guarantees logarithmic height. Fast insert/delete operations. Sets (std::set), maps (std::map) in C++. Treaps Probabilistically balanced. Simple insert/delete operations. Data structures requiring random balancing. B-trees Optimized for disk operations. File systems, databases.