foo.cc: In function 'int main()':
foo.cc:6:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&a);
     ~~~~~^~~~~~~~~

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

{"receive":"2020-05-27T02:31:53.822Z","handle":"2020-05-27T02:31:53.822Z","cache_start":"2020-05-27T02:31:53.828Z","read_cases":"2020-05-27T02:31:54.741Z","judge":"2020-05-27T02:31:54.741Z","done":"2020-05-27T02:31:54.840Z"}