// Retrieves the next aggregator name on aggregators 'set'.
 bool get_next_aggregator_name(char** aggregator){
     if (agg_it == aggregators.end()){
         return false;
     }
     *aggregator = strdup(agg_it->c_str());
     agg_it++;
     return true;
 }
int main()
{ 
	while(cin >> s)
	{ 
		tam = s.length();
		backtracking(0);

		for(it=possiveis.begin(); it!=possiveis.end(); it++)
			printf("%s\n",it->c_str());
		printf("\n");

		possiveis.clear();
		s1.clear();
	}
   return 0;
}