import { LinkedNode } from 'src/list';
import { BinaryTreeNode } from 'src/tree/binaryTreeNode';
import { CompareFn } from '..';
/**
 * @internal
 */
export declare function bubbleUp<T>(index: number, compareFn: CompareFn<T>, array: Array<T>): void;
/**
 * @internal
 */
export declare function heapify<T>(compareFn: CompareFn<T>, array: T[]): void;
/**
 * @internal
 */
export declare function mergeKSorted<T>(compareFn: CompareFn<T>, lists: LinkedNode<T>[]): LinkedNode<T>;
/**
 * @internal
 */
export declare function sinkDown<T>(index: number, compareFn: CompareFn<T>, array: Array<T>): void;
/**
 * See: https://en.wikipedia.org/wiki/Skew_heap#Merging_two_heaps
 *
 * @param compareFn - A function used to determine the order of the heap.
 *
 * It is expected to return:
 * - A negative value if first argument < second argument
 * - Zero if first argument == second argument
 * - A positive value if first argument > second argument
 * @param heaps - An iterable of heaps to merge
 *
 * @returns The new heap
 */
export declare function skewMerge<T>(compareFn: CompareFn<T>, heaps: (BinaryTreeNode<T> | undefined)[]): BinaryTreeNode<T> | undefined;