make-github-pseudonymous-again / js-bst

:seedling: Binary search tree library in JavaScript

🌱 @aureooms/js-bst

Binary search tree data structures for JavaScript. See docs. Parent is @aureooms/js-data-structures.

Description

This README regroups projects focusing on implementing search tree data structures with JavaScript. This project itself does not contain any code.

👶 Children

• @aureooms/js-red-black-tree
• @aureooms/js-splay-tree
• @aureooms/js-avl-tree
• 2-3 tree
• 2-3-4 tree
• AA tree
• Scapegoat tree
• Treap
• Randomized binary search tree

📜 Reference

• https://en.wikipedia.org/wiki/Self-balancing_binary_search_tree#Implementations
• http://opendatastructures.org/ods-java/7_Random_Binary_Search_Tree.html
• https://github.com/mikolalysenko/functional-red-black-tree

js-bst's Issues

hasBinarySearchProperty

import {isSorted} from '@aureooms/js-sort';
const hasBinarySearchProperty = (compare, tree) => {
    const array = [...tree];
    return isSorted(compare, array, 0, array.length);
};
const hasBinarySearchPropertyAndDoesNotContainDuplicates = (compare, tree) => {
    const strictCompare = (a,b) => compare(a,b) <= 0 ? -1 : 1;
    // const strictCompare = (a,b) => compare(a,b) < 0 ? -1 : 1; // ugly because the choice of `<=` vs `<` depends on the implementation of `hasBinarySearchProperty` and actually does not work in the general case
    return hasBinarySearchProperty(strictCompare, tree);

const hasBinarySearchProperty = (compare, node, left = undefined, right = undefined) => {
    if (node === null) return true;
    if (left !== undefined && compare(node.key, left) < 0) return false;
    if (right !== undefined && compare(node.key, right) > 0) return false;
    //     if (right !== undefined && compare(right, node.key) < 0) return false; // if using the `strictCompare` trick
    return hasBinarySearchProperty(compare, node.left, left, node.key) && hasBinarySearchProperty(compare, node.right, node.key, right);
};

const hasBinarySearchPropertyAndDoesNotContainDuplicates = (compare, node, left = undefined, right = undefined) => {
    if (node === null) return true;
    if (left !== undefined && compare(node.key, left) <= 0) return false;
    if (right !== undefined && compare(node.key, right) >= 0) return false;
    return hasBinarySearchProperty(compare, node.left, left, node.key) && hasBinarySearchProperty(compare, node.right, node.key, right);
};

See https://en.wikipedia.org/wiki/Binary_search_tree#Verification

Day–Stout–Warren algorithm

https://en.wikipedia.org/wiki/Day%E2%80%93Stout%E2%80%93Warren_algorithm

Scapegoat tree

Red-black tree

Treap

http://opendatastructures.org/ods-java/7_2_Treap_Randomized_Binary.html

define binary search tree abstract data type

• documentation + spec repository
• test repository and test refinement

2-3 tree

AVL tree

• https://www.youtube.com/watch?v=FNeL18KsWPc
• http://kukuruku.co/hub/cpp/avl-trees

Splay tree

2-3-4 tree

https://en.wikipedia.org/wiki/2%E2%80%933%E2%80%934_tree

AA tree

Randomized BST

http://kukuruku.co/hub/cpp/randomized-binary-search-trees