foo.cc: In function 'int main()':
foo.cc:74:4: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
    for(int j=1;j<=n;j++)
    ^~~
foo.cc:76:6: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
      printf("\n");
      ^~~~~~
foo.cc:54:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d",&n);
    ~~~~~^~~~~~~~~
foo.cc:60:11: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
      scanf("%d",&r);
      ~~~~~^~~~~~~~~

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

{"receive":"2020-08-07T12:42:15.149Z","handle":"2020-08-07T12:42:15.153Z","cache_start":"2020-08-07T12:42:15.241Z","read_cases":"2020-08-07T12:42:15.426Z","judge":"2020-08-07T12:42:15.430Z","done":"2020-08-07T12:42:16.819Z"}