asdf.js

function decipherThis(str) {
  
  const alphabet = ['a', 'b', 'c', 'd','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z']
  
  const index = alphabet.reduce((acc, letter) => {
    const uppercase = letter.toUpperCase()
    acc[letter.charCodeAt(0)] = letter
    acc[uppercase.charCodeAt(0)] = uppercase
    return acc
  }, {})
  
  const words = str.split(' ')
  
  const sentence = words.map((word) => {
    const charCode = word.match(/\d+/)
    const wordMatch = word.match(/[a-z]+/)
    const reversedWord = wordMatch ? wordMatch[0] : ""
    const partialWord = reversedWord.split("").reverse().join('')
    return index[charCode] + partialWord
  })
  
  return sentence.join(' ')
  
};