public @Nullable AbstractBlockWrapper getLeftRespNeighbor(@NotNull AbstractBlockWrapper block) {
    int index = getLeftRespNeighborIndex(block);
    if (index == -1) {
      return null;
    }
    else {
      return myBlocks.get(index);
    }
  }
public @Nullable AbstractBlockWrapper getLeftRespNeighbor(@NotNull AbstractBlockWrapper block)