const hyphenate = (word) => {
let originalArr = word.split(''); //word in its original form
let arr = word.toLowerCase().split(''); //word with all lower cased
let newarray = [];
for(i=0; i<arr.length; i++){
if (arr[i] !== 'a' && arr[i+1] !== 'a' //chars.includes(arr[i]) || chars.includes(arr[i + 1])
&& arr[i] !== 'e' && arr[i+1] !== 'e'
&& arr[i] !== 'i' && arr[i+1] !== 'i'
&& arr[i] !== 'u' && arr[i+1] !== 'u'
&& arr[i] !== 'o' && arr[i+1] !== 'o'
&& arr[i] !== 'y' && arr[i+1] !== 'y'
&& arr[i] !== ' ' && arr[i+1] !== ' ') {
newarray.push(originalArr[i])
newarray.push('-')
} else{
newarray.push(originalArr[i])
}
}
if(newarray[newarray.length-1] === "-") newarray.pop()
return newarray.join('')
}
console.log(hyphenate('hello world'))
