/in/foo.cc: In function 'int main()':
/in/foo.cc:13:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while(j<v.size()){
         ~^~~~~~~~~
/in/foo.cc:19:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<v.size();i++){
              ~^~~~~~~~~