src/heapify.js

import {siftdown, Heap} from './core/index.js';

/**
 * Builds a heap in O(n) operations.
 *
 * @param {function} compare the comparison function
 * @param {array} x the array where the heap is stored
 *
 */

export default function heapify(compare, x) {
	const n = x.length;

	for (let k = (n / 2) | 0; k; ) {
		siftdown(compare, x, 0, n, --k);
	}

	return new Heap(compare, x);
}