/in/foo.cc: In member function 'void PolyLinkNode::Add(PolyLinkNode)':
/in/foo.cc:40:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for (j = 0; j < v.size(); j++)
                         ~~^~~~~~~~~~
/in/foo.cc:48:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if (j >= v.size())
                 ~~^~~~~~~~~~~
/in/foo.cc:51:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < v.size() - 1; i++)
                         ~~^~~~~~~~~~~~~~
/in/foo.cc:53:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for (int j = 0; j < v.size() - 1 - i; j++)
                             ~~^~~~~~~~~~~~~~~~~~
/in/foo.cc:59:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < v.size(); i++)
                         ~~^~~~~~~~~~
/in/foo.cc: In member function 'void PolyLinkNode::Mul(PolyLinkNode)':
/in/foo.cc:70:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < v.size(); i++)
                         ~~^~~~~~~~~~
/in/foo.cc:72:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for (int j = 0; j < P.v.size(); j++)
                             ~~^~~~~~~~~~~~
/in/foo.cc:76:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 for (int k = 0; k < tmp.size(); k++)
                                 ~~^~~~~~~~~~~~
/in/foo.cc:83:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 if (k >= tmp.size())
                     ~~^~~~~~~~~~~~~
/in/foo.cc:87:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < tmp.size() - 1; i++)
                         ~~^~~~~~~~~~~~~~~~
/in/foo.cc:89:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for (int j = 0; j < tmp.size() - 1 - i; j++)
                             ~~^~~~~~~~~~~~~~~~~~~~
/in/foo.cc:95:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < tmp.size(); i++)
                         ~~^~~~~~~~~~~~
/in/foo.cc:83:23: warning: 'k' may be used uninitialized in this function [-Wmaybe-uninitialized]
                 if (k >= tmp.size())
                     ~~^~~~~~~~~~~~~