View Compilation Error

0_0_38367391_26216.cpp: In member function 'std::vector<long long int> Aho_Corasick_automaton::query(std::string)':
0_0_38367391_26216.cpp:75:16: error: could not convert 'ans' from 'long long int' to 'std::vector<long long int>'
         return ans;
                ^