export declare class SortedSet { items: string[]; hash: { [key: string]: number; }; values: { [key: string]: number; }; indexes: { [key: string]: number; }; constructor(); private swap; private less; private bubbleUp; private bubbleDown; add(item: string, value: number): void; pop(): string; isOpen(item: string): boolean; isClose(item: string): boolean; isEmpty(): boolean; }