code: private static void createInputDirectory(FileSystem fs, 
                                             Path dir,
                                             Pentomino pent,
                                             int depth
                                             ) throws IOException {
      fs.mkdirs(dir);
      List<int[]> splits = pent.getSplits(depth);
      PrintStream file = 
        new PrintStream(new BufferedOutputStream
                        (fs.create(new Path(dir, "part1")), 64*1024));
      for(int[] prefix: splits) {
        for(int i=0; i < prefix.length; ++i) {
          if (i != 0) {
            file.print(',');          
          }
          file.print(prefix[i]);
        }
        file.print('\n');
      }
      file.close();
    }
docs: Create the input file with all of the possible combinations of the
  given depth.
  @param fs the filesystem to write into
  @param dir the directory to write the input file into
  @param pent the puzzle
  @param depth the depth to explore when generating prefixes