foo.cc: In function 'int main()':
foo.cc:4:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&a,&b);
  ~~~~~^~~~~~~~~~~~~~

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

{"receive":"2020-08-08T14:55:56.569Z","handle":"2020-08-08T14:55:56.569Z","cache_start":"2020-08-08T14:55:56.576Z","read_cases":"2020-08-08T14:55:56.701Z","judge":"2020-08-08T14:55:56.702Z","done":"2020-08-08T14:55:56.792Z"}