System.out.println("#Process sentence " + sent_id);
HyperGraph hg_test = dhg_test.readHyperGraph();
//if(sent_id==1)System.exit(1);
//generate a unique nbest of strings based on viterbi cost
ArrayList<String> nonUniqueNbestStrings = new ArrayList<String>();
kbest_extractor.lazyKBestExtractOnHG(hg_test, null, topN, sent_id, nonUniqueNbestStrings);
double max_prob = Double.NEGATIVE_INFINITY;
String max_string = "";
//chech if the sentence is too long