private int getDistance(final int idxStart, final List<String> lines) {
    if (idxStart >= myLines.size()) return lines.size();
    int cnt = 0;
    for (int i = idxStart; i < myLines.size() && cnt < lines.size(); i++, cnt++) {
      if (! myLines.get(i).equals(lines.get(cnt))) return (lines.size() - cnt);
    }
    return lines.size() - cnt;
  }
private int getDistance(final int idxStart, final List<String> lines)