916.js

/** ------------------------------------------------------------------------------
 * 
 * 916. Word Subsets
 * Topics: Array, Hash Table
 * https://leetcode.com/problems/word-subsets/?envType=daily-question&envId=2025-01-10
 * 
 ------------------------------------------------------------------------------ */
/**
 * @param {string[]} words1
 * @param {string[]} words2
 * @return {string[]}
 */
var wordSubsets = function (words1, words2) {
  let ans = []
  let newArr = new Array(words2.length)
  let arr = new Array(26).fill(0)
  for (let i = 0; i < words2.length; i++) {
    let newArr = new Array(26).fill(0)
    for (let j of words2[i]) {
      newArr[j.charCodeAt(0) - 97]++
      arr[j.charCodeAt(0) - 97] = Math.max(arr[j.charCodeAt(0) - 97], newArr[j.charCodeAt(0) - 97])
    }
  }
  for (let i of words1) {
    let narr = new Array(26).fill(0)
    for (let j of i) {
      narr[j.charCodeAt(0) - 97]++
    }
    let canTake = true
    for (let i = 0; i < 26; i++) {
      if (narr[i] < arr[i]) {
        canTake = false
        break
      }
    }
    if (canTake) {
      ans.push(i)
    }
  }
  return ans
}

var wordSubsets = function (words1, words2) {
  let getFreq = (word) => {
    let currFreq = new Array(26).fill(0)
    for (let letter of word) {
      currFreq[letter.charCodeAt(0) - "a".charCodeAt(0)]++
    }
    return currFreq
  }

  let maxFreq = new Array(26).fill(0)
  for (let word of words2) {
    let wordFreq = getFreq(word)
    for (let i = 0; i < 26; i++) {
      maxFreq[i] = Math.max(wordFreq[i], maxFreq[i])
    }
  }
  let isUniv = (word) => {
    let wordFreq = getFreq(word)
    for (let i = 0; i < 26; i++) {
      if (wordFreq[i] < maxFreq[i]) {
        return false
      }
    }
    return true
  }

  return words1.filter(isUniv)
}

console.log(wordSubsets(["amazon", "apple", "facebook", "google", "leetcode"], ["lo", "eo"]))