foo.cc: In function 'int main()':
foo.cc:7:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ~~~~~^~~~~~~~~
foo.cc:9:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d",&a[i]);
    ~~~~~^~~~~~~~~~~~
foo.cc:10:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&b);
  ~~~~~^~~~~~~~~

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

{"receive":"2020-07-10T07:27:25.921Z","handle":"2020-07-10T07:27:25.921Z","cache_start":"2020-07-10T07:27:25.927Z","read_cases":"2020-07-10T07:27:26.035Z","judge":"2020-07-10T07:27:26.036Z","done":"2020-07-10T07:27:27.455Z"}