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export default function firstUniqChar(s: string): number {    const cnts: Record<string, number> = {};    for (const w of (s)) {        const arr = (cnts[w] ?? 0);
        cnts[w] = arr + 1;    }
    for (const [i, w] of Array.prototype.entries.call(s)) {        if (cnts[w] === 1) {            return i;        }    }    return -1;}