ics::pair<int,int> stats (const DTN& root) {
  ics::pair<int,int> pair(0,0);

  if (root.is_word)
	  ++pair.second;
  	  ++pair.first;
 	for (auto it = root.children.begin(); it != root.children.end(); ++it){
 		ics::pair<char,DTN> entry = *it;
 		ics::pair<int,int> temptemp =stats(entry.second);
 		pair.first += temptemp.first;
 		pair.second += temptemp.second;
 	}
   return pair;

}