Input: s = "aaaaaaaaaaaabbbbbcdd',  t = 'abcdd'Expected Output: "abbbbbcdd"

class Solution {  /**   * @param {string} s   * @param {string} t   * @return {string}   */  minWindow(s, t) {    if (t.length > s.length) return '';    let substring = '';    const map = new Map();    const set = new Set();    for (let i = 0; i < t.length; i++) {      map.set(t[i], (map.get(t[i]) ?? 0) + 1);      set.add(t[i]);    }    let startIndex = 0;    for (let endIndex = 0; endIndex < s.length; endIndex++) {      if (!map.has(s[endIndex])) continue;      const nextCount = map.get(s[endIndex]) - 1;      map.set(s[endIndex], nextCount);      if (nextCount === 0) set.delete(s[endIndex]);      else set.add(s[endIndex]);      while (map.get(s[startIndex]) < 0 || (!map.has(s[startIndex]) && startIndex < endIndex)) {        if (map.get(s[startIndex]) < 0) {          const nextCount = map.get(s[startIndex]) + 1;          map.set(s[startIndex], nextCount);          if (nextCount === 0) set.delete(s[startIndex]);        }        startIndex++;      }      if (        set.size === 0 &&        (substring.length === 0 || endIndex + 1 - startIndex < substring.length)      ) {        substring = s.slice(startIndex, endIndex + 1);      }    }    return substring;  }}