foo.cc: In function 'void DFS(int, int, int)':
foo.cc:23:39: warning: iteration 4 invokes undefined behavior [-Waggressive-loop-optimizations]
   23 |         int tmp_x = x + next_step[i][0];
      |                         ~~~~~~~~~~~~~~^
foo.cc:15:18: note: within this loop
   15 |     for(int i=0;i<5;i++)
      |                 ~^~
foo.cc: In function 'int main()':
foo.cc:60:8: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   60 |     DFS(0,x,y);
      |     ~~~^~~~~~~
foo.cc:60:8: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]

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