foo.cc: In function 'int main()':
foo.cc:9:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %lf",&n,&r);
                       ^
foo.cc:10:56: 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("%lf %lf",&x[i],&y[i]);
                                                        ^

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

{"receive":"2020-04-10T05:48:37.030Z","handle":"2020-04-10T05:48:37.030Z","cache_start":"2020-04-10T05:48:37.036Z","read_cases":"2020-04-10T05:48:37.168Z","judge":"2020-04-10T05:48:37.171Z","done":"2020-04-10T05:48:38.630Z"}