/in/foo.cc: In function 'int main()':
/in/foo.cc:5:10: warning: variable 's' set but not used [-Wunused-but-set-variable]
  int n,g,s,d;
          ^
/in/foo.cc:5:12: warning: variable 'd' set but not used [-Wunused-but-set-variable]
  int n,g,s,d;
            ^