/in/foo.cc: In function 'void Output(std::vector<int>, std::vector<int>, int)':
/in/foo.cc:15:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = 0; i < id.size(); i++)
                   ~~^~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:66:10: error: 'gets_s' was not declared in this scope
  gets_s(s);
          ^