/in/foo.cc: In function 'int main()':
/in/foo.cc:9:6: warning: unused variable 'i' [-Wunused-variable]
  int i = 0;
      ^
/in/foo.cc: In function 'void score(std::vector<char>&)':
/in/foo.cc:29:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (i = 0; i < ori.size(); i++) {
               ~~^~~~~~~~~~~~
/in/foo.cc:60:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (i = 0; i < out.size(); i++) {
              ~~^~~~~~~~~~~~