/in/foo.cc: In member function 'void gjd::Add(std::vector<int>&)':
/in/foo.cc:34:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while(i<v.size()&&i<v2.size())
         ~^~~~~~~~~
/in/foo.cc:34:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while(i<v.size()&&i<v2.size())
                     ~^~~~~~~~~~
/in/foo.cc:41:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while(i<v.size())
         ~^~~~~~~~~
/in/foo.cc:48:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while(i<v2.size())
         ~^~~~~~~~~~
/in/foo.cc: In member function 'void gjd::Sub(std::vector<int>)':
/in/foo.cc:64:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while(i<v.size()&&i<v1.size())
         ~^~~~~~~~~
/in/foo.cc:64:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while(i<v.size()&&i<v1.size())
                     ~^~~~~~~~~~
/in/foo.cc: In member function 'void gjd::Mul(int)':
/in/foo.cc:84:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while(i<v.size())
         ~^~~~~~~~~