/in/foo.c: In function 'main':
/in/foo.c:11:2: error: unknown type name 'Student'; use 'struct' keyword to refer to the type
  Student ss[100000];
  ^~~~~~~
  struct 
/in/foo.c:15:23: error: request for member 'id' in something not a structure or union
   scanf("%d%d", &ss[i].id, &ss[i].score);
                       ^
/in/foo.c:15:34: error: request for member 'score' in something not a structure or union
   scanf("%d%d", &ss[i].id, &ss[i].score);
                                  ^
/in/foo.c:17:25: error: request for member 'id' in something not a structure or union
  printf("%d %d\n", ss[k].id, ss[k].score);
                         ^
/in/foo.c:17:35: error: request for member 'score' in something not a structure or union
  printf("%d %d\n", ss[k].id, ss[k].score);
                                   ^