foo.cc: In function 'int main()':
foo.cc:34:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%lld%lld",&n,&m);
  ~~~~~^~~~~~~~~~~~~~~~~~
foo.cc:38:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%lld%lld%lld",&k,&l,&r);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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

{"receive":"2020-08-08T13:14:53.761Z","handle":"2020-08-08T13:14:53.761Z","cache_start":"2020-08-08T13:14:53.770Z","read_cases":"2020-08-08T13:14:53.929Z","judge":"2020-08-08T13:14:53.932Z","done":"2020-08-08T13:14:55.057Z"}