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export default class FrontMiddleBackQueue {    #queue: Array<number> = [];
    pushFront(val: number): void {        this.#queue.unshift(val);    }
    pushMiddle(val: number): void {        this.#queue.splice(Math.floor(this.#queue.length / 2), 0, val);    }
    pushBack(val: number): void {        this.#queue.push(val);    }
    popFront(): number {        return this.#queue.shift() ?? -1;    }
    popMiddle(): number {        // console.log(this)        if (this.#queue.length === 0) return -1;        // console.log(this.queue.length)        const mid = Math.floor(this.#queue.length / 2) -            Number(!(this.#queue.length % 2));        // console.log(mid)        const result = this.#queue[mid];        // console.log(result)        this.#queue.splice(mid, 1);        // console.log(this)        return result;    }
    popBack(): number {        return this.#queue.pop() ?? -1;    }}