foo.cc: In function 'int main()':
foo.cc:39:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&k,&n);
                        ^
foo.cc:47:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d%d",&x,&y);
                                ^

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

{"receive":"2020-03-28T07:21:23.294Z","handle":"2020-03-28T07:21:23.294Z","cache_start":"2020-03-28T07:21:23.301Z","read_cases":"2020-03-28T07:21:23.465Z","judge":"2020-03-28T07:21:23.469Z","done":"2020-03-28T07:21:24.450Z"}