Find the longest words from cubes with letters

helpers.js

const allWords = require('russian-words');

function getCubesLettersHeap(cubes) {
  return cubes.reduce((acc, cube) => {
    const letters = cube.split('');
    letters.forEach(letter => {
      acc[letter] = acc[letter]? acc[letter] + 1 : 1;
    });
    return acc;
  }, {});
}

function getWordLettersHeap(word) {
  return word
    .split('')
    .reduce((acc, letter) => {
      acc[letter] = acc[letter] ? acc[letter] + 1 : 1;
      return acc;
    }, {});
}


function findWords(cubes) {
  const cubesLettersHeap = getCubesLettersHeap(cubes);

  return allWords
    .filter(word => {
      if (word.length !== cubes.length) return false;
      const wordLettersHeap = getWordLettersHeap(word);
      return Object.keys(wordLettersHeap).every(key => {
        return cubesLettersHeap[key] && cubesLettersHeap[key] > wordLettersHeap[key];
      });
    });
}

module.exports = {
  findWords,
};

index.js

const {findWords} = require('./helpers');

const cubes = ['нмксрп', 'нмксрп', 'нгдбзж', 'ктфчло', 'нзджгб', 'пшдиам', 'бцйхлш', 'пшдиам', 'аоуэыи', 'вьиеср', 'аёиеюя', 'аоуэыи'];
const result = findWords(cubes);
console.log(result);