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export default function strStr(haystack: string, needle: string): number {    if (needle.length == 0) return 0;    // return haystack.search(needle)
    // const index=haystack.indexOf(needle[0])
    // if(index===-1){return -1}
    const spl = Array.from(haystack);    const ind = [...spl.entries()]        .filter(([_i, a]) => a === needle[0])        .map(([i]) => i);
    if (ind.length === 0) return -1;    for (const i of ind) {        if (needle === haystack.slice(i, i + needle.length)) {            return i;        }    }    return -1;}