low = mid;
      } else {
        return mid; // allRequired[mid] = centerFloor, so we can't get closer than that
      }
    }

    // Now pick the closest of the two candidates. Note that there is no rounding here.
    if (from + to - allRequired[low] - allRequired[high] > 0) {
      return high;
    } else {
      return low;
    }
  }