public int getSumOfInterval(int left, int right) {
    if (left < 0 || left > right || right > size()) {
      throw new IllegalArgumentException("Size is: " + size() + ", but interval is: (" + left + ", " + right + ")");
    }
    if (left == size()) return 0;

    int startIndex = myStartIndexMap.getLongIndex(left);
    int sum = 0;
    for (int i = 0; i < right - left; i++) {
      int sizeOf = getNextStartIndex(startIndex) - startIndex;
      sum += ByteArrayUtils.readDelta(startIndex, sizeOf, myCompressedDeltas);
      startIndex += sizeOf;
    }
    return sum;
  }
public int getSumOfInterval(int left, int right)