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export default class StreamRank {    #bit = new BinaryIndexTree(50001);    constructor() {}
    track(x: number): void {        this.#bit.update(x + 1, 1);    }
    getRankOfNumber(x: number): number {        return this.#bit.query(x + 1);    }}export class BinaryIndexTree {    static lowbit(x: number) {        return x & -x;    }    #tree: number[];    constructor(public size: number) {        this.#tree = Array(size + 1).fill(0);    }    update(i: number, x: number) {        for (let p = i; p <= this.size; p += BinaryIndexTree.lowbit(p)) {            this.#tree[p] += x;        }    }    query(n: number) {        let ans = 0;        for (let p = n; p > 0; p -= BinaryIndexTree.lowbit(p)) {            ans += this.#tree[p];        }        return ans;    }}