Class AVLTree<K, V, R>

Represents a self-balancing AVL (Adelson-Velsky and Landis) Tree. This tree extends BST and performs rotations on add/delete to maintain balance.

// basic AVLTree creation and add operation
// Create a simple AVLTree with initial values
const tree = new AVLTree([5, 2, 8, 1, 9]);

tree.print();
// _2___
// / \
// 1 _8_
// / \
// 5 9

// Verify the tree maintains sorted order
console.log([...tree.keys()]); // [1, 2, 5, 8, 9];

// Check size
console.log(tree.size); // 5;

// Add a new element
tree.add(3);
console.log(tree.size); // 6;
console.log([...tree.keys()]); // [1, 2, 3, 5, 8, 9];
// AVLTree has and get operations
const tree = new AVLTree<number>([11, 3, 15, 1, 8, 13, 16, 2, 6, 9, 12, 14, 4, 7, 10, 5]);

// Check if element exists
console.log(tree.has(6)); // true;
console.log(tree.has(99)); // false;

// Get node by key
const node = tree.getNode(6);
console.log(node?.key); // 6;

// Verify tree is balanced
console.log(tree.isAVLBalanced()); // true;
// AVLTree delete and balance verification
const tree = new AVLTree([11, 3, 15, 1, 8, 13, 16, 2, 6, 9, 12, 14, 4, 7, 10, 5]);

// Delete an element
tree.delete(10);
console.log(tree.has(10)); // false;

// Tree should remain balanced after deletion
console.log(tree.isAVLBalanced()); // true;

// Size decreased
console.log(tree.size); // 15;

// Remaining elements are still sorted
const keys = [...tree.keys()];
console.log(keys); // [1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16];
// AVLTree for university ranking system with strict balance
interface University {
name: string;
rank: number;
students: number;
}

// AVLTree provides highest search efficiency with strict balance
// (every node's left/right subtrees differ by at most 1 in height)
const universityTree = new AVLTree<number, University>([
[1, { name: 'MIT', rank: 1, students: 1200 }],
[5, { name: 'Stanford', rank: 5, students: 1800 }],
[3, { name: 'Harvard', rank: 3, students: 2300 }],
[2, { name: 'Caltech', rank: 2, students: 400 }],
[4, { name: 'CMU', rank: 4, students: 1500 }]
]);

// Quick lookup by rank
const mit = universityTree.get(1);
console.log(mit?.name); // 'MIT';

const cmulevel = universityTree.getHeight(4);
console.log(typeof cmulevel); // 'number';

// Tree maintains strict balance during insertions and deletions
console.log(universityTree.isAVLBalanced()); // true;

// Add more universities
universityTree.add(6, { name: 'Oxford', rank: 6, students: 2000 });
console.log(universityTree.isAVLBalanced()); // true;

// Delete and verify balance is maintained
universityTree.delete(2);
console.log(universityTree.has(2)); // false;
console.log(universityTree.isAVLBalanced()); // true;

// Get all remaining universities in rank order
const remainingRanks = [...universityTree.keys()];
console.log(remainingRanks); // [1, 3, 4, 5, 6];
console.log(universityTree.size); // 5;
// Find elements in a range
// In interval queries, AVL trees, with their strictly balanced structure and lower height, offer better query efficiency, making them ideal for frequent and high-performance interval queries. In contrast, Red-Black trees, with lower update costs, are more suitable for scenarios involving frequent insertions and deletions where the requirements for interval queries are less demanding.
type Datum = { timestamp: Date; temperature: number };
// Fixed dataset of CPU temperature readings
const cpuData: Datum[] = [
{ timestamp: new Date('2024-12-02T00:00:00'), temperature: 55.1 },
{ timestamp: new Date('2024-12-02T00:01:00'), temperature: 56.3 },
{ timestamp: new Date('2024-12-02T00:02:00'), temperature: 54.8 },
{ timestamp: new Date('2024-12-02T00:03:00'), temperature: 57.2 },
{ timestamp: new Date('2024-12-02T00:04:00'), temperature: 58.0 },
{ timestamp: new Date('2024-12-02T00:05:00'), temperature: 59.4 },
{ timestamp: new Date('2024-12-02T00:06:00'), temperature: 60.1 },
{ timestamp: new Date('2024-12-02T00:07:00'), temperature: 61.3 },
{ timestamp: new Date('2024-12-02T00:08:00'), temperature: 62.0 },
{ timestamp: new Date('2024-12-02T00:09:00'), temperature: 63.5 },
{ timestamp: new Date('2024-12-02T00:10:00'), temperature: 64.0 },
{ timestamp: new Date('2024-12-02T00:11:00'), temperature: 62.8 },
{ timestamp: new Date('2024-12-02T00:12:00'), temperature: 61.5 },
{ timestamp: new Date('2024-12-02T00:13:00'), temperature: 60.2 },
{ timestamp: new Date('2024-12-02T00:14:00'), temperature: 59.8 },
{ timestamp: new Date('2024-12-02T00:15:00'), temperature: 58.6 },
{ timestamp: new Date('2024-12-02T00:16:00'), temperature: 57.4 },
{ timestamp: new Date('2024-12-02T00:17:00'), temperature: 56.2 },
{ timestamp: new Date('2024-12-02T00:18:00'), temperature: 55.7 },
{ timestamp: new Date('2024-12-02T00:19:00'), temperature: 54.5 },
{ timestamp: new Date('2024-12-02T00:20:00'), temperature: 53.2 },
{ timestamp: new Date('2024-12-02T00:21:00'), temperature: 52.8 },
{ timestamp: new Date('2024-12-02T00:22:00'), temperature: 51.9 },
{ timestamp: new Date('2024-12-02T00:23:00'), temperature: 50.5 },
{ timestamp: new Date('2024-12-02T00:24:00'), temperature: 49.8 },
{ timestamp: new Date('2024-12-02T00:25:00'), temperature: 48.7 },
{ timestamp: new Date('2024-12-02T00:26:00'), temperature: 47.5 },
{ timestamp: new Date('2024-12-02T00:27:00'), temperature: 46.3 },
{ timestamp: new Date('2024-12-02T00:28:00'), temperature: 45.9 },
{ timestamp: new Date('2024-12-02T00:29:00'), temperature: 45.0 }
];

// Create an AVL tree to store CPU temperature data
const cpuTemperatureTree = new AVLTree<Date, number, Datum>(cpuData, {
toEntryFn: ({ timestamp, temperature }) => [timestamp, temperature]
});

// Query a specific time range (e.g., from 00:05 to 00:15)
const rangeStart = new Date('2024-12-02T00:05:00');
const rangeEnd = new Date('2024-12-02T00:15:00');
const rangeResults = cpuTemperatureTree.rangeSearch([rangeStart, rangeEnd], node => ({
minute: node ? node.key.getMinutes() : 0,
temperature: cpuTemperatureTree.get(node ? node.key : undefined)
}));

console.log(rangeResults); // [
// { minute: 5, temperature: 59.4 },
// { minute: 6, temperature: 60.1 },
// { minute: 7, temperature: 61.3 },
// { minute: 8, temperature: 62 },
// { minute: 9, temperature: 63.5 },
// { minute: 10, temperature: 64 },
// { minute: 11, temperature: 62.8 },
// { minute: 12, temperature: 61.5 },
// { minute: 13, temperature: 60.2 },
// { minute: 14, temperature: 59.8 },
// { minute: 15, temperature: 58.6 }
// ];

Type Parameters

  • K = any

    The type of the key.

  • V = any

    The type of the value.

  • R = any

    The type of the raw data object (if using toEntryFn).

    1. Height-Balanced: Each node's left and right subtrees differ in height by no more than one.
    2. Automatic Rebalancing: AVL trees rebalance themselves automatically during insertions and deletions.
    3. Rotations for Balancing: Utilizes rotations (single or double) to maintain balance after updates.
    4. Order Preservation: Maintains the binary search tree property where left child values are less than the parent, and right child values are greater.
    5. Efficient Lookups: Offers O(log n) search time, where 'n' is the number of nodes, due to its balanced nature.
    6. Complex Insertions and Deletions: Due to rebalancing, these operations are more complex than in a regular BST.
    7. Path Length: The path length from the root to any leaf is longer compared to an unbalanced BST, but shorter than a linear chain of nodes.

Hierarchy (view full)

Implements

  • IBinaryTree<K, V, R>

Constructors

  • Creates an instance of AVLTree.

    Type Parameters

    • K = any
    • V = any
    • R = any

    Parameters

    • OptionalkeysNodesEntriesOrRaws: Iterable<
          | undefined
          | null
          | K
          | R
          | AVLTreeNode<K, V>
          | [undefined | null | K, undefined | V], any, any> = []

      An iterable of items to add.

    • Optionaloptions: AVLTreeOptions<K, V, R>

      Configuration options for the AVL tree.

    Returns AVLTree<K, V, R>

    Time O(N log N) (from addMany with balanced add). Space O(N).

Properties

_comparator: Comparator<K>

The comparator function used to determine the order of keys in the tree.

Time O(1) Space O(1)

Accessors

  • get comparator(): Comparator<K>
  • Gets the comparator function used by the tree.

    Returns Comparator<K>

    The comparator function.

    Time O(1)

  • get isDuplicate(): boolean
  • Gets whether the tree allows duplicate keys.

    Returns boolean

    True if duplicates are allowed, false otherwise.

    Time O(1)

  • get isMapMode(): boolean
  • Gets whether the tree is in Map mode.

    Returns boolean

    True if in Map mode, false otherwise.

    In Map mode (default), values are stored in an external Map, and nodes only hold keys. If false, values are stored directly on the nodes. Time O(1)

  • get store(): Map<K, undefined | V>
  • Gets the external value store (used in Map mode).

    Returns Map<K, undefined | V>

    The map storing key-value pairs.

    Time O(1)

  • get toEntryFn(): undefined | ToEntryFn<K, V, R>
  • Gets the function used to convert raw data objects (R) into [key, value] entries.

    Returns undefined | ToEntryFn<K, V, R>

    The conversion function.

    Time O(1)

Methods

  • (Protected) Calculates the balance factor (height(right) - height(left)).

    Parameters

    Returns number

    The balance factor (positive if right-heavy, negative if left-heavy).

    Time O(1) (assumes heights are stored).

  • (Protected) Traverses up the tree from the specified node, updating heights and performing rotations as needed.

    Parameters

    • node:
          | undefined
          | null
          | K
          | AVLTreeNode<K, V>
          | [undefined | null | K, undefined | V]

      The node to start balancing from (e.g., the newly inserted node or parent of the deleted node).

    Returns void

    Time O(log N) (O(H)), as it traverses the path to root. Space O(H) for the path array.

  • (Protected) Core bound search implementation supporting all parameter types. Unified logic for both lowerBound and upperBound. Resolves various input types (Key, Node, Entry, Predicate) using parent class utilities.

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
          | NodePredicate<BSTNode<K, V>>

      The key, node, entry, or predicate function to search for.

    • isLower: boolean

      True for lowerBound (>=), false for upperBound (>).

    • iterationType: IterationType

      The iteration type (RECURSIVE or ITERATIVE).

    Returns undefined | BSTNode<K, V>

    The first matching node, or undefined if no such node exists.

  • (Protected) Binary search for bound by key with pruning optimization. Performs standard BST binary search, choosing left or right subtree based on comparator result. For lowerBound: finds first node where key >= target. For upperBound: finds first node where key > target.

    Parameters

    • key: K

      The target key to search for.

    • isLower: boolean

      True for lowerBound (>=), false for upperBound (>).

    • iterationType: IterationType

      The iteration type (RECURSIVE or ITERATIVE).

    Returns undefined | BSTNode<K, V>

    The first node matching the bound condition, or undefined if none exists.

  • (Protected) In-order traversal search by predicate. Falls back to linear in-order traversal when predicate-based search is required. Returns the first node that satisfies the predicate function. Note: Predicate-based search cannot leverage BST's binary search optimization. Time Complexity: O(n) since it may visit every node.

    Parameters

    • predicate: NodePredicate<BSTNode<K, V>>

      The predicate function to test nodes.

    • iterationType: IterationType

      The iteration type (RECURSIVE or ITERATIVE).

    Returns undefined | BSTNode<K, V>

    The first node satisfying predicate, or undefined if none found.

  • (Protected) Compares two keys using the tree's comparator and reverse setting.

    Parameters

    • a: K

      The first key.

    • b: K

      The second key.

    Returns number

    A number (1, -1, or 0) representing the comparison.

    Time O(1) Space O(1)

  • (Protected) Creates a new instance of the same AVLTree constructor, potentially with different generic types.

    Type Parameters

    • TK = K
    • TV = V
    • TR = R

    Parameters

    • Optionaliter: Iterable<
          | undefined
          | null
          | TK
          | TR
          | AVLTreeNode<TK, TV>
          | [undefined | null | TK, undefined | TV], any, any> = []

      An iterable to populate the new tree.

    • Optionaloptions: Partial<AVLTreeOptions<TK, TV, TR>>

      Options for the new tree.

    Returns AVLTree<TK, TV, TR>

    A new AVLTree.

    Time O(N log N) (from constructor) due to processing the iterable.

  • (Private) Deletes a node by its key.

    Parameters

    • key: K

      The key of the node to delete.

    Returns boolean

    True if the node was found and deleted, false otherwise.

    Standard BST deletion algorithm. Time O(log N), O(N) worst-case. Space O(1).

  • Type Parameters

    Parameters

    • callback: C

      Function to call on nodes.

    • Optionalpattern: DFSOrderPattern

      Traversal order.

    • OptionalonlyOne: boolean

      Stop after first match.

    • OptionalstartNode:
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>

      Starting node.

    • OptionaliterationType: IterationType

      Traversal method.

    • OptionalincludeNull: boolean

      Include nulls.

    • OptionalshouldVisitLeft: ((node: undefined | null | BinaryTreeNode<K, V>) => boolean)

      Predicate to traverse left.

        • (node): boolean
        • Parameters

          Returns boolean

    • OptionalshouldVisitRight: ((node: undefined | null | BinaryTreeNode<K, V>) => boolean)

      Predicate to traverse right.

        • (node): boolean
        • Parameters

          Returns boolean

    • OptionalshouldVisitRoot: ((node: undefined | null | BinaryTreeNode<K, V>) => boolean)

      Predicate to visit root.

        • (node): boolean
        • Parameters

          Returns boolean

    • OptionalshouldProcessRoot: ((node: undefined | null | BinaryTreeNode<K, V>) => boolean)

      Predicate to process root.

        • (node): boolean
        • Parameters

          Returns boolean

    Returns ReturnType<C>[]

    Array of callback results.

  • (Protected) Recursive helper for toVisual.

    Parameters

    • node: undefined | null | BinaryTreeNode<K, V>

      The current node.

    • options: BinaryTreePrintOptions

      Print options.

    Returns NodeDisplayLayout

    Layout information for this subtree.

    Time O(N), Space O(N*H) or O(N^2)

  • (Protected) Extracts the key from a key, node, or entry.

    Parameters

    • keyNodeOrEntry:
          | undefined
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>

      The item.

    Returns undefined | null | K

    The extracted key.

    Time O(1)

  • (Protected) Binary search for floor by key with pruning optimization. Performs standard BST binary search, choosing left or right subtree based on comparator result. Finds first node where key <= target.

    Parameters

    • key: K

      The target key to search for.

    • iterationType: IterationType

      The iteration type (RECURSIVE or ITERATIVE).

    Returns undefined | BSTNode<K, V>

    The first node with key <= target, or undefined if none exists.

    Time O(h) where h is tree height.

  • (Protected) In-order traversal search for floor by predicate. Falls back to linear in-order traversal when predicate-based search is required. Returns the last node that satisfies the predicate function.

    Parameters

    • predicate: NodePredicate<BSTNode<K, V>>

      The predicate function to test nodes.

    • iterationType: IterationType

      The iteration type (RECURSIVE or ITERATIVE).

    Returns undefined | BSTNode<K, V>

    The last node satisfying predicate (highest key), or undefined if none found.

    Time Complexity: O(n) since it may visit every node. Space Complexity: O(h) for recursion, O(h) for iterative stack.

  • (Protected) Gets the iterator for the tree (default in-order).

    Parameters

    • Optionalnode: null | BinaryTreeNode<K, V> = ...

      The node to start iteration from.

    Returns IterableIterator<[K, undefined | V], any, any>

    An iterator for [key, value] pairs.

    Time O(N) for full iteration. O(H) to get the first element. Space O(H) for the iterative stack. O(H) for recursive stack.

  • (Protected) Converts a key, node, or entry into a standardized [node, value] tuple.

    Parameters

    • keyNodeOrEntry:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]

      The input item.

    • Optionalvalue: V

      An optional value (used if input is just a key).

    Returns [OptNode<BSTNode<K, V>>, undefined | V]

    A tuple of [node, value].

    Time O(1)

  • (Protected) Binary search for lower by key with pruning optimization. Performs standard BST binary search, choosing left or right subtree based on comparator result. Finds first node where key < target.

    Parameters

    • key: K

      The target key to search for.

    • iterationType: IterationType

      The iteration type (RECURSIVE or ITERATIVE).

    Returns undefined | BSTNode<K, V>

    The first node with key < target, or undefined if none exists.

    Time O(h) where h is tree height.

  • (Protected) In-order traversal search for lower by predicate. Falls back to linear in-order traversal when predicate-based search is required. Returns the node that satisfies the predicate and appears last in in-order traversal.

    Parameters

    • predicate: NodePredicate<BSTNode<K, V>>

      The predicate function to test nodes.

    • iterationType: IterationType

      The iteration type (RECURSIVE or ITERATIVE).

    Returns undefined | BSTNode<K, V>

    The last node satisfying predicate (highest key < target), or undefined if none found.

    Time Complexity: O(n) since it may visit every node. Space Complexity: O(h) for recursion, O(h) for iterative stack.

  • (Protected) Sets a value in the external store (Map mode).

    Parameters

    • key: undefined | null | K

      The key.

    • value: undefined | V

      The value.

    Returns false | Map<K, undefined | V>

    True if successful.

    Time O(1) (average for Map.set).

  • (Protected) Recalculates and updates the height of a node based on its children's heights.

    Parameters

    Returns void

    Time O(1) (assumes children's heights are correct).

  • Default iterator yielding [key, value] entries.

    Parameters

    • Rest...args: any[]

    Returns IterableIterator<[K, undefined | V], any, any>

    Iterator of [K, V].

    Time O(n) to iterate, Space O(1)

  • Adds a new node to the AVL tree and balances the tree path.

    Parameters

    • keyNodeOrEntry:
          | undefined
          | null
          | K
          | AVLTreeNode<K, V>
          | [undefined | null | K, undefined | V]

      The key, node, or entry to add.

    • Optionalvalue: V

      The value, if providing just a key.

    Returns boolean

    True if the addition was successful, false otherwise.

    Time O(log N) (O(H) for BST add + O(H) for _balancePath). Space O(H) for path/recursion.

  • Adds multiple items to the tree.

    Parameters

    • keysNodesEntriesOrRaws: Iterable<R | BTNRep<K, V, BSTNode<K, V>>, any, any>

      An iterable of items to add.

    • Optionalvalues: Iterable<undefined | V, any, any>

      An optional parallel iterable of values.

    • OptionalisBalanceAdd: boolean = true

      If true, builds a balanced tree from the items.

    • OptionaliterationType: IterationType = ...

      The traversal method for balanced add (recursive or iterative).

    Returns boolean[]

    An array of booleans indicating the success of each individual add operation.

    If isBalanceAdd is true, sorts the input and builds a balanced tree. Time O(N log N) (due to sort and balanced add). If false, adds items one by one. Time O(N * H), which is O(N^2) worst-case. Space O(N) for sorting and recursion/iteration stack.

  • Returns the first key with a value >= target. Equivalent to Java TreeMap.ceiling. Time Complexity: O(log n) average, O(h) worst case. Space Complexity: O(h) for recursion, O(1) for iteration.

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
          | NodePredicate<BSTNode<K, V>>

    Returns undefined | K

  • Returns the first node with a key >= target and applies callback. Time Complexity: O(log n) average, O(h) worst case. Space Complexity: O(h) for recursion, O(1) for iteration.

    Type Parameters

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
          | NodePredicate<BSTNode<K, V>>
    • callback: C
    • OptionaliterationType: IterationType

    Returns ReturnType<C>

  • Clones the tree.

    Returns this

    A new, cloned instance of the tree.

    Time O(N * M), where N is the number of nodes and M is the tree size during insertion (due to bfs + add, and add is O(M)). Space O(N) for the new tree and the BFS queue.

  • Creates a new, empty tree of the same type and configuration.

    Parameters

    • Optionaloptions: Partial<BinaryTreeOptions<K, V, R>>

      Optional overrides for the new tree's options.

    Returns this

    A new, empty tree instance.

    Time O(1) (excluding options cloning), Space O(1)

  • Deletes a node from the AVL tree and re-balances the tree.

    Parameters

    • keyNodeOrEntry:
          | undefined
          | null
          | K
          | AVLTreeNode<K, V>
          | [undefined | null | K, undefined | V]

      The node to delete.

    Returns BinaryTreeDeleteResult<AVLTreeNode<K, V>>[]

    An array containing deletion results.

    Time O(log N) (O(H) for BST delete + O(H) for _balancePath). Space O(H) for path/recursion.

  • Deletes nodes that match a key, node, entry, predicate, or range.

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
          | NodePredicate<BSTNode<K, V>>
          | Range<K>

      The search criteria. Can be one of:

      • A key (type K): searches for exact key match using the comparator.
      • A BSTNode: searches for the matching node in the tree.
      • An entry tuple: searches for the key-value pair.
      • A NodePredicate function: tests each node and returns true for matches.
      • A Range object: searches for nodes whose keys fall within the specified range (inclusive/exclusive based on range settings).
      • null or undefined: treated as no match, returns empty results.
    • onlyOne: boolean = false

      If true, stops the search after finding the first match and only deletes that one node. If false (default), searches for and deletes all matching nodes.

    • startNode:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V] = ...

      The node to start the search from. Can be:

      • A key, node, or entry: the method resolves it to a node and searches from that subtree.
      • null or undefined: defaults to the root, searching the entire tree.
      • Default value: this._root (the tree's root).
    • iterationType: IterationType = ...

      Controls the internal traversal implementation:

      • 'RECURSIVE': uses recursive function calls for traversal.
      • 'ITERATIVE': uses explicit stack-based iteration.
      • Default: this.iterationType (the tree's default iteration mode).

    Returns BinaryTreeDeleteResult<BSTNode<K, V>>[]

    A Map<K, boolean> containing the deletion results:

    • Key: the matched node's key.
    • Value: true if the deletion succeeded, false if it failed (e.g., key not found during deletion phase).
    • If no nodes match the search criteria, the returned map is empty.

    Time Complexity: O(N) for search + O(M log N) for M deletions, where N is tree size. Space Complexity: O(M) for storing matched nodes and result map.

  • Returns (undefined | K)[]

  • Type Parameters

    Parameters

    • callback: C
    • Optionalpattern: DFSOrderPattern
    • OptionalonlyOne: boolean
    • OptionalstartNode:
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
    • OptionaliterationType: IterationType

    Returns ReturnType<C>[]

  • Ensures the input is a node. If it's a key or entry, it searches for the node.

    Parameters

    • keyNodeOrEntry:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]

      The item to resolve to a node.

    • OptionaliterationType: IterationType = ...

      The traversal method to use if searching.

    Returns OptNode<BSTNode<K, V>>

    The resolved node, or undefined if not found.

    Time O(log N) (height of the tree), O(N) worst-case.

  • Iterate over [key, value] pairs (may yield undefined values).

    Returns IterableIterator<[K, undefined | V], any, any>

    Iterator of [K, V | undefined].

    Time O(n), Space O(1)

  • Test whether all entries satisfy the predicate.

    Parameters

    • predicate: EntryCallback<K, undefined | V, boolean>

      (key, value, index, self) => boolean.

    • OptionalthisArg: any

      Optional this for callback.

    Returns boolean

    true if all pass; otherwise false.

    Time O(n), Space O(1)

  • Creates a new tree containing only the entries that satisfy the predicate.

    Parameters

    • predicate: EntryCallback<K, undefined | V, boolean>

      A function to test each [key, value] pair.

    • OptionalthisArg: unknown

      this context for the predicate.

    Returns this

    A new, filtered tree.

    Time O(N * M), where N is nodes in this tree, and M is size of the new tree during insertion (O(N) iteration + O(M) add for each item). Space O(N) for the new tree.

  • Find the first entry that matches a predicate.

    Parameters

    • callbackfn: EntryCallback<K, undefined | V, boolean>

      (key, value, index, self) => boolean.

    • OptionalthisArg: any

      Optional this for callback.

    Returns undefined | [K, undefined | V]

    Matching [key, value] or undefined.

    Time O(n), Space O(1)

  • Returns the first key with a value <= target. Equivalent to Java TreeMap.floor. Time Complexity: O(log n) average, O(h) worst case. Space Complexity: O(h) for recursion, O(1) for iteration.

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
          | NodePredicate<BSTNode<K, V>>

    Returns undefined | K

  • Returns the first node with a key <= target and applies callback. Time Complexity: O(log n) average, O(h) worst case. Space Complexity: O(h) for recursion, O(1) for iteration.

    Type Parameters

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
          | NodePredicate<BSTNode<K, V>>
    • callback: C
    • OptionaliterationType: IterationType

    Returns ReturnType<C>

  • Visit each entry, left-to-right.

    Parameters

    • callbackfn: EntryCallback<K, undefined | V, void>

      (key, value, index, self) => void.

    • OptionalthisArg: any

      Optional this for callback.

    Returns void

    Time O(n), Space O(1)

  • Gets the value associated with a key.

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>

      The key, node, or entry to get the value for.

    • OptionalstartNode:
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V> = ...

      The node to start searching from (if not in Map mode).

    • OptionaliterationType: IterationType = ...

      The traversal method (if not in Map mode).

    Returns undefined | V

    The associated value, or undefined.

    Time O(log N), For BST, Red-Black Tree, and AVL Tree subclasses, the worst-case time is O(log N). Time O(1) if in Map mode. O(N) if not in Map mode (uses getNode). Space O(1) if in Map mode. O(H) or O(N) otherwise.

  • Gets the depth of a node (distance from startNode).

    Parameters

    • dist:
          | undefined
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>

      The node to find the depth of.

    • OptionalstartNode:
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V> = ...

      The node to measure depth from (defaults to root).

    Returns number

    The depth (0 if dist is startNode).

    Time O(H), where H is the depth of the dist node relative to startNode. O(N) worst-case. Space O(1).

  • Gets the maximum height of the tree (longest path from startNode to a leaf).

    Parameters

    • OptionalstartNode:
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V> = ...

      The node to start measuring from.

    • OptionaliterationType: IterationType = ...

      The traversal method.

    Returns number

    The height ( -1 for an empty tree, 0 for a single-node tree).

    Time O(N), as it must visit every node. Space O(H) for recursive stack (O(N) worst-case) or O(N) for iterative stack (storing node + depth).

  • Gets the minimum height of the tree (shortest path from startNode to a leaf).

    Parameters

    • OptionalstartNode:
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V> = ...

      The node to start measuring from.

    • OptionaliterationType: IterationType = ...

      The traversal method.

    Returns number

    The minimum height (-1 for empty, 0 for single node).

    Time O(N), as it must visit every node. Space O(H) for recursive stack (O(N) worst-case) or O(N) for iterative (due to depths Map).

  • Gets the first node matching a predicate.

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
          | NodePredicate<BSTNode<K, V>>

      The key, node, entry, or predicate function to search for.

    • OptionalstartNode: BSTNOptKeyOrNode<K, BSTNode<K, V>> = ...

      The node to start the search from.

    • OptionaliterationType: IterationType = ...

      The traversal method.

    Returns OptNode<BSTNode<K, V>>

    The first matching node, or undefined if not found.

    Time O(log N) if searching by key, O(N) if searching by predicate. Space O(log N) or O(N).

  • Gets all nodes matching a predicate.

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>
          | NodePredicate<BinaryTreeNode<K, V>>

      The key, node, entry, or predicate function to search for.

    • OptionalonlyOne: boolean

      If true, stops after finding the first match.

    • OptionalstartNode:
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>

      The node to start the search from.

    • OptionaliterationType: IterationType

      The traversal method.

    Returns BinaryTreeNode<K, V>[]

    An array of matching nodes.

    Time O(N) (via search). Space O(H) or O(N) (via search).

  • Checks if a node matching the predicate exists in the tree.

    Parameters

    • OptionalkeyNodeEntryOrPredicate:
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>
          | NodePredicate<BinaryTreeNode<K, V>>

      The key, node, entry, or predicate to check for.

    • OptionalstartNode:
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>

      The node to start the search from.

    • OptionaliterationType: IterationType

      The traversal method.

    Returns boolean

    True if a matching node exists, false otherwise.

    Time O(log N), For BST, Red-Black Tree, and AVL Tree subclasses, the worst-case time is O(log N). Time O(N) in the worst case (via search). Space O(H) or O(N) (via search).

  • Whether there exists an entry with the given value.

    Parameters

    • value: undefined | V

      Value to test.

    Returns boolean

    true if found; otherwise false.

    Time O(n), Space O(1)

  • Returns the first key with a value > target. Equivalent to Java TreeMap.higher. Time Complexity: O(log n) average, O(h) worst case. Space Complexity: O(h) for recursion, O(1) for iteration.

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
          | NodePredicate<BSTNode<K, V>>

    Returns undefined | K

  • Returns the first node with a key > target and applies callback. Time Complexity: O(log n) average, O(h) worst case. Space Complexity: O(h) for recursion, O(1) for iteration.

    Type Parameters

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
          | NodePredicate<BSTNode<K, V>>
    • callback: C
    • OptionaliterationType: IterationType

    Returns ReturnType<C>

  • Checks if the tree meets the AVL balance condition (height difference <= 1).

    Parameters

    • OptionaliterationType: IterationType = ...

      The traversal method.

    Returns boolean

    True if the tree is AVL balanced, false otherwise.

    Time O(N), as it must visit every node to compute height. Space O(log N) for recursion or O(N) for iterative map.

  • Checks if the tree is a valid Binary Search Tree (BST).

    Parameters

    • OptionalstartNode:
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V> = ...

      The node to start checking from.

    • OptionaliterationType: IterationType = ...

      The traversal method.

    Returns boolean

    True if it's a valid BST, false otherwise.

    Time O(N), as it must visit every node. Space O(H) for the call stack (recursive) or explicit stack (iterative), where H is the tree height (O(N) worst-case).

  • Checks if the given item is a [key, value] entry pair.

    Parameters

    • keyNodeOrEntry:
          | undefined
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>

      The item to check.

    Returns keyNodeOrEntry is BTNEntry<K, V>

    True if it's an entry, false otherwise.

    Time O(1), Space O(1)

  • Checks if a node is a leaf (has no real children).

    Parameters

    • keyNodeOrEntry:
          | undefined
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>

      The node to check.

    Returns boolean

    True if the node is a leaf, false otherwise.

    Time O(N) if a key/entry is passed (due to ensureNode). O(1) if a node is passed. Space O(1) or O(H) (from ensureNode).

  • Checks if the given item is the sentinel NIL node.

    Parameters

    • keyNodeOrEntry:
          | undefined
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>

      The item to check.

    Returns boolean

    True if it's the NIL node, false otherwise.

    Time O(1), Space O(1)

  • Checks if the tree is perfectly balanced.

    Parameters

    • OptionalstartNode:
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V> = ...

      The node to start checking from.

    Returns boolean

    True if perfectly balanced, false otherwise.

    A tree is perfectly balanced if the difference between min and max height is at most 1. Time O(N), as it requires two full traversals (getMinHeight and getHeight). Space O(H) or O(N) (from height calculation).

  • Checks if the given item is a Range object.

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>
          | NodePredicate<BinaryTreeNode<K, V>>
          | Range<K>

      The item to check.

    Returns keyNodeEntryOrPredicate is Range<K>

    True if it's a Range, false otherwise.

    Time O(1), Space O(1)

  • Checks if the given item is a raw data object (R) that needs conversion via toEntryFn.

    Parameters

    • keyNodeEntryOrRaw:
          | undefined
          | null
          | K
          | R
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>

      The item to check.

    Returns keyNodeEntryOrRaw is R

    True if it's a raw object, false otherwise.

    Time O(1), Space O(1)

  • Checks if the given key is valid (comparable).

    Parameters

    • key: any

      The key to validate.

    Returns key is K

    True if the key is valid, false otherwise.

    Time O(1)

  • Returns the first key with a value < target. Equivalent to Java TreeMap.lower. Time Complexity: O(log n) average, O(h) worst case. Space Complexity: O(h) for recursion, O(1) for iteration.

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
          | NodePredicate<BSTNode<K, V>>

    Returns undefined | K

  • Returns the first node with a key < target and applies callback. Time Complexity: O(log n) average, O(h) worst case. Space Complexity: O(h) for recursion, O(1) for iteration.

    Type Parameters

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
          | NodePredicate<BSTNode<K, V>>
    • callback: C
    • OptionaliterationType: IterationType

    Returns ReturnType<C>

  • Creates a new AVLTree by mapping each [key, value] pair.

    Type Parameters

    • MK = K

      New key type.

    • MV = V

      New value type.

    • MR = any

      New raw type.

    Parameters

    • callback: EntryCallback<K, undefined | V, [MK, MV]>

      A function to map each [key, value] pair.

    • Optionaloptions: Partial<BinaryTreeOptions<MK, MV, MR>>

      Options for the new AVLTree.

    • OptionalthisArg: unknown

      this context for the callback.

    Returns AVLTree<MK, MV, MR>

    A new, mapped AVLTree.

    Time O(N log N) (O(N) iteration + O(log M) add for each item into the new tree). Space O(N) for the new tree.

  • Merges another tree into this one by adding all its nodes.

    Parameters

    Returns void

    Time O(N * M), same as addMany, where N is the size of anotherTree and M is the size of this tree. Space O(M) (from add).

  • Rebuilds the tree to be perfectly balanced.

    Parameters

    • OptionaliterationType: IterationType = ...

      The traversal method for the initial node export.

    Returns boolean

    True if successful, false if the tree was empty.

    AVL trees are already height-balanced, but this makes them perfectly balanced (minimal height and all leaves at N or N-1). Time O(N) (O(N) for DFS, O(N) for sorted build). Space O(N) for node array and recursion stack.

  • Prints a visual representation of the tree to the console.

    Parameters

    • Optionaloptions: BinaryTreePrintOptions

      Options to control the output.

    • OptionalstartNode:
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V> = ...

      The node to start printing from.

    Returns void

    Time O(N) (via toVisual). Space O(N*H) or O(N^2) (via toVisual).

  • Reduce entries into a single accumulator.

    Type Parameters

    • U

    Parameters

    • callbackfn: ReduceEntryCallback<K, undefined | V, U>

      (acc, value, key, index, self) => acc.

    • initialValue: U

      Initial accumulator.

    Returns U

    Final accumulator.

    Time O(n), Space O(1)

  • Clears the tree and refills it with new items.

    Parameters

    • keysNodesEntriesOrRaws: Iterable<
          | undefined
          | null
          | K
          | R
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>, any, any>

      An iterable of items to add.

    • Optionalvalues: Iterable<undefined | V, any, any>

      An optional parallel iterable of values.

    Returns void

    Time O(N) (for clear) + O(N * M) (for addMany) = O(N * M). Space O(M) (from addMany).

  • Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
          | NodePredicate<BSTNode<K, V>>
          | Range<K>
    • OptionalonlyOne: boolean

    Returns (undefined | K)[]

  • Type Parameters

    Parameters

    • keyNodeEntryOrPredicate:
          | undefined
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
          | NodePredicate<BSTNode<K, V>>
          | Range<K>
    • onlyOne: boolean
    • callback: C
    • OptionalstartNode:
          | null
          | K
          | BSTNode<K, V>
          | [undefined | null | K, undefined | V]
    • OptionaliterationType: IterationType

    Returns ReturnType<C>[]

  • Adds or updates a new node to the tree.

    Parameters

    • keyNodeOrEntry:
          | undefined
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>

      The key, node, or entry to add or update.

    • Optionalvalue: V

      The value, if providing just a key.

    Returns boolean

    True if the addition was successful, false otherwise.

    Time O(log N), For BST, Red-Black Tree, and AVL Tree subclasses, the worst-case time is O(log N). This implementation adds the node at the first available position in a level-order (BFS) traversal. This is NOT a Binary Search Tree insertion. Time O(N), where N is the number of nodes. It must traverse level-by-level to find an empty slot. Space O(N) in the worst case for the BFS queue (e.g., a full last level).

  • Adds or updates multiple items to the tree.

    Parameters

    • keysNodesEntriesOrRaws: Iterable<
          | undefined
          | null
          | K
          | R
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V>, any, any>

      An iterable of items to add or update.

    • Optionalvalues: Iterable<undefined | V, any, any>

      An optional parallel iterable of values.

    Returns boolean[]

    An array of booleans indicating the success of each individual add operation.

    Time O(N * M), where N is the number of items to add and M is the size of the tree at insertion (due to O(M) add operation). Space O(M) (from add) + O(N) (for the inserted array).

  • Test whether any entry satisfies the predicate.

    Parameters

    • predicate: EntryCallback<K, undefined | V, boolean>

      (key, value, index, self) => boolean.

    • OptionalthisArg: any

      Optional this for callback.

    Returns boolean

    true if any passes; otherwise false.

    Time O(n), Space O(1)

  • Generates a string representation of the tree for visualization.

    Parameters

    • OptionalstartNode:
          | null
          | K
          | [undefined | null | K, undefined | V]
          | BinaryTreeNode<K, V> = ...

      The node to start printing from.

    • Optionaloptions: BinaryTreePrintOptions

      Options to control the output (e.g., show nulls).

    Returns string

    The string representation of the tree.

    Time O(N), visits every node. Space O(N*H) or O(N^2) in the worst case, as the string width can grow significantly.

  • Iterate over values only.

    Returns IterableIterator<undefined | V, any, any>

    Iterator of values.

    Time O(n), Space O(1)