/in/foo.cc: In function 'int findsum(int)':
/in/foo.cc:19:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  else for (int i=0;i<M[v].size();i++)
                    ~^~~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:47:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i=0;i<M[hd].size();i++)
                ~^~~~~~~~~~~~~
/in/foo.cc:55:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i=0;i<M[hd].size();i++)
                ~^~~~~~~~~~~~~
/in/foo.cc:57:4: warning: 'jilu' may be used uninitialized in this function [-Wmaybe-uninitialized]
    if(i!=jilu)
    ^~