// your code goes here
const s = "あ い&う え"
let out = s.replace(/&#(\d{1,5});/g, (match) => {
const num = parseInt(match.match(/&#(.+);/)[1])
return String.fromCharCode(num)
})
.split(/\s| /).join(" ")
console.log(out)
Ly8geW91ciBjb2RlIGdvZXMgaGVyZQpjb25zdCBzID0gIuOBgiYjMTYwO+OBhCYjMzg744GG44CA44GIIgoKbGV0IG91dCA9IHMucmVwbGFjZSgvJiMoXGR7MSw1fSk7L2csIChtYXRjaCkgPT4gewoJY29uc3QgbnVtID0gcGFyc2VJbnQobWF0Y2gubWF0Y2goLyYjKC4rKTsvKVsxXSkKCXJldHVybiBTdHJpbmcuZnJvbUNoYXJDb2RlKG51bSkKfSkKLnNwbGl0KC9cc3zjgIAvKS5qb2luKCIgIikKCmNvbnNvbGUubG9nKG91dCk=