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export default class MyStack {    #queue: number[] = [];
    push(x: number): void {        const length = this.#queue.length;        this.#queue.push(x);        for (let i = 0; i < length; i++) {            const first = this.#queue.shift();            if (typeof first == "undefined") {                throw new Error("queue is empty");            }            this.#queue.push(first);        }    }
    pop(): number {        const res = this.#queue.shift();        if (typeof res == "undefined") {            throw new Error("queue is empty");        }        return res;    }
    top(): number {        return this.#queue[0];    }
    empty(): boolean {        return this.#queue.length === 0;    }}