foo.cc: In function 'int main()':
foo.cc:11:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   11 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
foo.cc:14:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   14 |         scanf("%d%d%d",&a,&b,&c);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~

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