/in/foo.cc: In function 'lowprice* getLowPrice(int)':
/in/foo.cc:27:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<pfv.size();i++) {
                 ~^~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:60:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for(int j=0;j<vfp.size();j++) {
                         ~^~~~~~~~~~~