foo.cc:48:9: warning: missing terminating " character
  printf("\n);
         ^
foo.cc:48:9: error: missing terminating " character
  printf("\n);
         ^~~~~
foo.cc: In function 'bool dfs(int)':
foo.cc:17:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < strlen(op[t]); i++)
                  ~~^~~~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:49:2: error: expected primary-expression before 'return'
  return 0;
  ^~~~~~
foo.cc: In function 'bool dfs(int)':
foo.cc:38:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
foo.cc: In function 'int main()':
foo.cc:42:38: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for (int i = 0; i < 9; i++) scanf("%d", &dir[i]);
                                 ~~~~~^~~~~~~~~~~~~~~

自豪的采用 HydroJudger 进行评测(github.com/hydro-dev/HydroJudger)