/in/foo.cc: In function 'int main()':
/in/foo.cc:44:8: warning: 'sy' may be used uninitialized [-Wmaybe-uninitialized]
   44 |     dfs(tmp, (sx << 3) | sy, 1);
      |     ~~~^~~~~~~~~~~~~~~~~~~~~~~~
/in/foo.cc:28:13: note: 'sy' was declared here
   28 |     int sx, sy;
      |             ^~
/in/foo.cc:44:18: warning: 'sx' may be used uninitialized [-Wmaybe-uninitialized]
   44 |     dfs(tmp, (sx << 3) | sy, 1);
      |              ~~~~^~~~~
/in/foo.cc:28:9: note: 'sx' was declared here
   28 |     int sx, sy;
      |         ^~