function normalizeString(word) {

  word = word.toLowerCase()

  const result = normalizeString.memo[word]

  if (result) return result

  return normalizeString.memo[word] =

    [...word.replace(/\s/g, '')]

      .sort() + ''

}

normalizeString.memo = {}

const checkAnagram = (word, source) =>

  normalizeString(word) === normalizeString(source)

// try it out 

const target = 'adorn hair'

const anagrams = [

  'hoard rain',

  'hair radon',

  'hadron air',

  'hairdo ran',

  'radian rho',

  'au revoir fail'

];

anagrams.forEach(anigram => { 

  console.log(anigram, '=', checkAnagram(anigram, target))

})