Urlify the string

by Alex Myronov

JavaScript

const shift = (arr, length, index) => {
  //arr.push(undefined, undefined)

  let reverseIndex = length - 1
  while (reverseIndex - 2 > index) {
    arr[reverseIndex] = arr[reverseIndex - 2]
    reverseIndex--
  }
  return arr
}

const urlify = (str) => {
	let arr = str.split('')
  
  let length = arr.length
  let index = 0
  while (index < length) {
    if (arr[index] === ' ') {
    	length = length + 2
			arr = shift(arr, length, index)

     arr[index++] = '%' 
     arr[index++] = '2'
     arr[index++] = '0'
    } else {
      index++
    }
  }
  
	return arr.join('')
}

console.log(urlify('hey there you  '))