foo.cc: In function 'void dts::main()':
foo.cc:25:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   25 |         scanf("%d%lf",&n,&R);
      |         ~~~~~^~~~~~~~~~~~~~~
foo.cc:28:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   28 |             scanf("%lf%lf",&p[i].x,&p[i].y);
      |             ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

[Hydro](https://hydro.ac)提供评测服务