message: If an output file is specified, dump the neighbors array to it.
diff: #include <sstream>
  char * fname;
  +char * outfname;
  template < typename T >
  void verify_array(T* standard, T* expt, int n)
  @@ -195,6 +196,16 @@ void readPointsFile(char * fname,
  }
  }
  +void writeNeigborsFile(char * fname, int * neighbors, int n)
  +{
  + std::ofstream outfile(fname);
  + if (outfile.good()) {
  + for (int i = 0; i < n; ++i) {
  + outfile << neighbors[i] << std::endl;
  + }
  + }
  +}
  +
  TEST(quest_ann, file_query)
  {
  if (fname != nullptr) {
  @@ -232,6 +243,10 @@ TEST(quest_ann, file_query)
  verify_array(bfneighbor, idxneighbor, n);
  }
  + if (outfname != nullptr) {
  + writeNeigborsFile(outfname, idxneighbor, n);
  + }
  +
  delete [] bfneighbor;
  delete [] idxneighbor;
  }
  @@ -248,11 +263,15 @@ int main(int argc, char * argv[])
  {
  int result = 0;
  fname = nullptr;
  + outfname = nullptr;
  ::testing::InitGoogleTest(&argc, argv);
  if (argc > 1) {
  fname = argv[1];
  + if (argc > 2) {
  + outfname = argv[2];
  + }
  }
  UnitTestLogger logger; // create & initialize test logger,
  