/in/foo.cc: In function 'int main(int, char**)':
/in/foo.cc:11:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<shu.size();i++){
              ~^~~~~~~~~~~
/in/foo.cc:27:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if(dianwz+k>=shu.size()-1){
      ~~~~~~~~^~~~~~~~~~~~~~