foo.cc: In function 'int main()':
foo.cc:36:2: error: 'sort' was not declared in this scope; did you mean 'std::sort'?
   36 |  sort(student + 1, student + n + 1, compare);
      |  ^~~~
      |  std::sort
In file included from /usr/include/c++/9/algorithm:62,
                 from foo.cc:3:
/usr/include/c++/9/bits/stl_algo.h:4893:5: note: 'std::sort' declared here
 4893 |     sort(_RandomAccessIterator __first, _RandomAccessIterator __last,
      |     ^~~~
foo.cc:30:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   30 |  scanf("%d", &n);
      |  ~~~~~^~~~~~~~~~
foo.cc:33:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   33 |   scanf("%d %d %d", &student[i].c_score, &student[i].m_score, &student[i].e_score);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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