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export default function two_Sum(nums: number[], target: number): number[] {    const storeNumstoindex = new Map<number, number>();
    for (const [i, num1] of nums.entries()) {        const num2 = target - num1;        const index2 = storeNumstoindex.get(num2);        if (typeof index2 !== "undefined") {            return [i, index2];        } else {            storeNumstoindex.set(num1, i);        }    }    throw Error("should not go here");}