foo.cc: In function 'int main()':
foo.cc:15:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   15 |     scanf("%d%d", &n, &front);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~
foo.cc:19:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   19 |         scanf("%d", &x);
      |         ~~~~~^~~~~~~~~~

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