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export default function reverse(x: number): number {    if (0 <= x && x <= 9) return x;    if (Math.abs(x) > 2147483641) return 0;    if (x < 0) return -1 * reverse(-x);    let result = 0;
    while (x > 0) {        result = result * 10 + (x % 10);        if (result > 2 ** 31 - 1) return 0;        x /= 10;        x = Math.floor(x);    }    return result;}