@Override
    public String toString() {
      StringBuilder s = new StringBuilder();
      for (int i = 0; i < size; i++) {
        if (s.length() != 0) s.append(' ');
        if (newOffsets[i] != -1) {
          s.append('(').append(oldOffsets[i]).append("->").append(newOffsets[i]).append(')');
        }
        else {
          s.append('[').append(oldOffsets[i]).append(']');
        }
      }
      return s.toString();
    }
@Override
    public String toString()