function bubbleSort(arr) {
  for (let i = 0; i < arr.length; i++) {
    for (let j = i + 1; j < arr.length; j++) {
      if (arr[i] > arr[j]) {
        [ arr[i], arr[j] ] = [ arr[j], arr[i] ];
      }
    }
  }

  return arr;
}

console.log(bubbleSort([12,12,33,4,15, 14 ,6, 8,7,28, 19, 30, 40]))