Solve the NYTimes Spelling Bee challenge - https://www.nytimes.com/puzzles/spelling-bee

spelling-bee-solver.js

const wordListPath = require('word-list'); // https://github.com/sindresorhus/word-list
const readlines = require('gen-readlines'); // https://github.com/neurosnap/gen-readlines

const isSuperset = (set, subset) => {
  for (const elem of subset) {
    if (!set.has(elem)) {
      return false;
    }
  }
  return true;
}

const solve = function*(letters) {
  const requiredLetter = letters[0];
  const letterSet = new Set(letters);

  for (const line of readlines.fromFile(wordListPath)) {
    if (line.length < 4) {
      continue;
    }

    const word = line.toString();

    const wordSet = new Set(word.split(''));

    if (wordSet.has(requiredLetter) && isSuperset(letterSet, wordSet)) {
      yield word;
    }
  }
};

for (const solution of solve('cfaplte'.split(''))) {
  console.log(solution);
}