foo.cc: In function 'int main()':
foo.cc:32:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n);
  ~~~~~^~~~~~~~~~
foo.cc:34:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &arr[i].u);
   ~~~~~^~~~~~~~~~~~~~~~~
foo.cc:37:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &arr[i].v);
   ~~~~~^~~~~~~~~~~~~~~~~

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

{"receive":"2020-07-11T23:43:38.137Z","handle":"2020-07-11T23:43:38.137Z","cache_start":"2020-07-11T23:43:38.144Z","read_cases":"2020-07-11T23:43:38.269Z","judge":"2020-07-11T23:43:38.273Z","done":"2020-07-11T23:43:38.864Z"}