function binarySearch(numbers, element) {

  let left = 0;
  let right = numbers.length - 1;
  let pivot = Math.floor((left + right) / 2);
  while(left < pivot && pivot < right) {
    if(element < numbers[pivot]) {
      right = pivot;
    } else {
      left = pivot;
    }
    pivot = Math.floor((left + right) / 2);
  }
  if(element === numbers[pivot]) {
    return pivot;
  }
  return -1;
}