/in/foo.cc: In function 'int main()':
/in/foo.cc:52:27: warning: 'end_y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   if (nowx == end_x&&nowy == end_y)
                      ~~~~~^~~~~~~~
/in/foo.cc:52:12: warning: 'end_x' may be used uninitialized in this function [-Wmaybe-uninitialized]
   if (nowx == end_x&&nowy == end_y)
       ~~~~~^~~~~~~~
/in/foo.cc:41:10: warning: 'begin_y' may be used uninitialized in this function [-Wmaybe-uninitialized]
  begin.y = begin_y;
  ~~~~~~~~^~~~~~~~~
/in/foo.cc:40:10: warning: 'begin_x' may be used uninitialized in this function [-Wmaybe-uninitialized]
  begin.x = begin_x;
  ~~~~~~~~^~~~~~~~~