foo.cc: In function 'int main(int, const char**)':
foo.cc:36:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&n,&k);
     ~~~~~^~~~~~~~~~~~~~
foo.cc:37:44: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for(int i=1;i<=n;i++) scanf("%d",&a[i]),sum+=a[i];
                           ~~~~~~~~~~~~~~~~~^~~~~~~~~~

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

{"receive":"2020-05-30T04:46:19.763Z","handle":"2020-05-30T04:46:19.763Z","cache_start":"2020-05-30T04:46:19.769Z","read_cases":"2020-05-30T04:46:20.296Z","judge":"2020-05-30T04:46:20.300Z","done":"2020-05-30T04:46:21.262Z"}