/in/foo.cc: In function 'int bs(int, int)':
/in/foo.cc:19:22: warning: 'ys' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return (ys*(a/ys)*(b/ys));
                    ~~^~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:19:22: warning: 'ys' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return (ys*(a/ys)*(b/ys));
                    ~~^~~~
/in/foo.cc:6:6: note: 'ys' was declared here
  int ys, lsb = b;
      ^~