/in/foo.cc: In function 'bool check(int)':
/in/foo.cc:37:12: warning: unused variable 'x' [-Wunused-variable]
  int i, j, x, y, lmin, lmax, rmin, rmax;
            ^
/in/foo.cc:37:15: warning: unused variable 'y' [-Wunused-variable]
  int i, j, x, y, lmin, lmax, rmin, rmax;
               ^