addressable-binary-heaps/dist/cjs/core/heap.util.js

A versatile TypeScript library for addressable binary heaps, delivering optimized and scalable min-heap and max-heap implementations, seamlessly supporting both object-oriented and functional paradigms.

'use strict';

/**
 * Returns the index of the parent of a heap array element.
 * In a binary heap, parent index is calculated as `floor((i-1)/2)`.
 *
 * @param index - The index of heap array element.
 * @returns The index of the parent element, or `-1` if root.
 */
function getParentIndex(index) {
    return 0 >= index ? -1 : Math.floor((index - 1) / 2);
}
/**
 * Returns the index of the left child of a heap array element.
 * In a binary heap, left child index is calculated as `2i + 1`.
 *
 * @param index - The index of heap array element.
 * @returns The index of the left child element.
 */
function getLeftChildIndex(index) {
    return 2 * index + 1;
}
/**
 * Returns the index of the right child of a heap array element.
 * In a binary heap, right child index is calculated as `2i + 2`.
 *
 * @param index - The index of heap array element.
 * @returns The index of the right child element.
 */
function getRightChildIndex(index) {
    return 2 * index + 2;
}
/**
 * Swaps the position of two elements in a heap array.
 *
 * @typeParam H - The type of heap.
 * @param instance - The heap instance.
 * @param firstIndex - The array index of the first element.
 * @param secondIndex - The array index of the second element.
 */
function swapHeapNodes(instance, firstIndex, secondIndex) {
    const node = instance[firstIndex];
    instance[firstIndex] = instance[secondIndex];
    instance[secondIndex] = node;
    instance.indices.set(instance[firstIndex], firstIndex);
    instance.indices.set(instance[secondIndex], secondIndex);
}

exports.getLeftChildIndex = getLeftChildIndex;
exports.getParentIndex = getParentIndex;
exports.getRightChildIndex = getRightChildIndex;
exports.swapHeapNodes = swapHeapNodes;