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function RandomizedSet() {    const value_to_index = new Map<number, number>();    const nums: number[] = [];    return {        insert(val: number): boolean {            if (value_to_index.has(val)) return false;            const index = nums.length;            nums.push(val);            value_to_index.set(val, index);            return true;        },        remove(val: number): boolean {            if (!value_to_index.has(val)) return false;            const index = value_to_index.get(val);            if (typeof index === "undefined") {                throw Error("accident");            }            const last = nums.at(-1);            if (typeof last === "undefined") {                throw Error("accident");            }            nums[index] = last;            value_to_index.set(last, index);            nums.pop();            value_to_index.delete(val);            return true;        },        getRandom(): number {            return nums[Math.floor(Math.random() * nums.length)];        },    };}
type RandomizedSet = ReturnType<typeof RandomizedSet>;export default RandomizedSet;