/in/shortestP2P.cc: In member function 'void ShortestP2P::distance(unsigned int, unsigned int)':
/in/shortestP2P.cc:30:28: error: comparison between signed and unsigned integer expressions [-Werror=sign-compare]
           for(int k = 1; k < graph_edge[j].size(); k++)
                          ~~^~~~~~~~~~~~~~~~~~~~~~
/in/shortestP2P.cc:52:28: error: comparison between signed and unsigned integer expressions [-Werror=sign-compare]
           for(int k = 1; k < graph_edge[j].size(); k++)
                          ~~^~~~~~~~~~~~~~~~~~~~~~
cc1plus: all warnings being treated as errors