/in/foo.cc: In function 'int makea(int, int)':
/in/foo.cc:21:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:24:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 for (i=1; i<=s.length(); i++)
           ~^~~~~~~~~~~~