/in/foo.cc: In function 'int main()':
/in/foo.cc:72:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             while(!v.empty()&&i<q.size())
                               ~^~~~~~~~~
/in/foo.cc:78:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for(i=0;i<q.size();++i)
                     ~^~~~~~~~~