vowelDoubler.js

const vowelDoubler = array => {
  const vowels = ['a', 'e', 'i', 'o', 'u'];
  let resultLength = array.length;
  for (let i = 0; i < array.length; i += 1) {
    if (vowels.includes(array[i])) {
      resultLength += 1;
    }
  }
  let offset = resultLength - array.length;
  for (let i = resultLength - 1; i >= 0; i -= 1) {
    if (vowels.includes(array[i - offset])) {
      array[i] = array[i - offset];
      array[i - 1] = array[i - offset];
      // offset += 1;
      // temp2 = array[i + 2];
      // array[i + 2] = temp;
      offset -= 1;
      i -= 1;
    } else {
      array[i] = array[i - offset];
    }
  }
  return array;
};