/in/foo.cc: In function 'int main()':
/in/foo.cc:31:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < str.size(); i++)
                  ~~^~~~~~~~~~~~
/in/foo.cc: In function 'int turn(char)':
/in/foo.cc:16:9: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return x;
         ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:36:14: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
   q[x][y][z] = i+1;
   ~~~~~~~~~~~^~~~~
/in/foo.cc:36:14: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
/in/foo.cc:36:14: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]