/in/foo.cc: In function 'int main()':
/in/foo.cc:51:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for(int k = 0; k < g[i].size(); k++)
                            ~~^~~~~~~~~~~~~
/in/foo.cc:62:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int j = 0; j < g[i].size(); j++)
                        ~~^~~~~~~~~~~~~
/in/foo.cc:71:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for(int k = 0; k < ans[i].size(); k++)
                            ~~^~~~~~~~~~~~~~~