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export default function convert(s: string, numRows: number): string {    if (numRows === 1) return s;
    const rows: string[] = new Array(numRows).fill("");    let curRow = 0;
    let goingDown = false;
    for (const c of s) {        rows[curRow] += c;        if (curRow === 0 || curRow == numRows - 1) {            goingDown = !goingDown;        }        curRow += goingDown ? 1 : -1;    }    return rows.join("");}