Main.cc: In function ‘int main()’:
Main.cc:31:15: error: request for member ‘mark’ in ‘mark’, which is of non-class type ‘int [10005]’
   31 |     sort(mark.mark+n);
      |               ^~~~
Main.cc:15:10: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   15 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
Main.cc:18:14: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   18 |         scanf("%d %d",&x[i],&y[i]);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~