@lichtblick/avl

Adelson-Velsky-Landis (AVL) self-balancing binary trees in TypeScript

Introduction

AVL trees are self-balancing binary trees that are commonly used to implement sorted sets. In addition to the common insertion, deletion, and retrieval operations, this implementation also supports range queries, greater than, and less than searches.

Usage

import { AVLTree } from "@lichtblick/avl";

const tree = new AVLTree<number, string>();
tree.set(0, "zero");
tree.set(1, "1");
tree.set(1, "one");
tree.set(3, "three");
tree.set(2, "two");
tree.delete(0);
console.log(tree.has(0)); // false
console.log(tree.get(1)); // "one"
console.log(tree.size); // 3
console.log(tree.minEntry()); // [1, "one"]
console.log(tree.maxEntry()); // [3, "three"]
console.log(tree.findLessThan(2)); // [1, "one"]
console.log(tree.findGreaterThanOrEqual(2)); // [2, "two"]
tree.forEach((value, key) => console.log(value)); // "one" "two" "three"
tree.range(2, 3, (value, key) => console.log(value)); // "two" "three"
console.log(tree.pop()); // [3, "three"]
console.log(tree.shift()); // [1, "one"]
tree.clear();

// Use a custom comparator for non-Number keys
const bigintTree = new AVLTree<bigint, string>((a, b) => Number(a - b));
bigintTree.set(1n, "one");

Alternatives

avl - Optional support for duplicate keys, but return values can mutate after delete() calls, missing range query optimization, no find[Less/Greater]Than[OrEqual] queries, no iterators, and naming conventions do not follow ES6 container patterns.

License

@lichtblick/avl is licensed under the MIT License.

Releasing

1. Run yarn version --[major|minor|patch] to bump version
2. Run git push && git push --tags to push new tag
3. GitHub Actions will take care of the rest