cassidoo newsletter problem solution

solution.js

function charNumSort(array) {
  return array
    .map((word) => ({ word, characters: new Set(word.toLowerCase().split('')) }))
    .sort((a, b) => {
     if (a.characters.size === b.characters.size) {
       return b.word.length - a.word.length
     }
     return a.characters.size - b.characters.size
    })
    .map(({ word }) => word)
}