export declare class PrefixIntervalTree {
    _size: number;
    _half: number;
    _heap: Int32Array;
    constructor(xs: any[]);
    set(index: number, value: any): void;
    get(index: number): any;
    getSize(): number;
    sumUntil(end: number): number;
    sumTo(inclusiveEnd: number): number;
    sum(begin: number, end: number): number;
    greatestLowerBound(t: number): number;
    greatestStrictLowerBound(t: number): number;
    leastUpperBound(t: number): number;
    leastStrictUpperBound(t: number): number;
    static uniform(size: number, initialValue: any): PrefixIntervalTree;
    static empty(size: number, initialValue: any): PrefixIntervalTree;
}