/in/foo.cc: In function 'int main()':
/in/foo.cc:43:24: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::vector<int>::size_type {aka long unsigned int}' [-Wformat=]
  printf("%d\n",v.size());
                ~~~~~~~~^
/in/foo.cc:44:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<v.size();i++) printf("%d\n",v[i]);
              ~^~~~~~~~~