/in/foo.cc: In function 'int main()':
/in/foo.cc:6:6: warning: unused variable 'y' [-Wunused-variable]
  int y=0,n=0;
      ^
/in/foo.cc:6:10: warning: unused variable 'n' [-Wunused-variable]
  int y=0,n=0;
          ^