foo.cc: In function 'int main()':
foo.cc:22:8: warning: unused variable 'n' [-Wunused-variable]
   22 |   char n[100];
      |        ^
foo.cc:24:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   24 |   scanf("%s", student->s);
      |   ~~~~~^~~~~~~~~~~~~~~~~~

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