code: public Iterator<WordCooccurrence> execute(Collection<String> inputDirs)
              throws Exception {
  
          HadoopJobResults results = job.run(inputDirs);
          return new WordCooccurrenceIterator(
              results.getFileSystem(), results.getResults().iterator());
      }
docs: Exceutes the word co-occurrence counting job on the corpus files in the
  input directory using the current Hadoop instance, returning an iterator
  over all the occurrences frequences found in the corpus.
  
  @param inputDirs a list of directories on the Hadoop distributed file
  system containing all the corpus files that will be processed
  
  @return an iterator over the unique {@link WordCooccurrence} counts found
  in the corpus.  Note that if two words co-occur the same distance
  apart multiple times, only one {@code WordCooccurrence} is
  returned, where the number of co-occurrences is reflected by the
  the {@link WordCooccurrence#getCount() getCount()} method.
  
  @throws Exception if Hadoop throws an {@code Exception} during its
  execution or if the resulting output files cannot be read.