foo.cc: In function 'int main()':
foo.cc:8:15: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    8 |     for (scanf("%lld", &t); t--;)
      |          ~~~~~^~~~~~~~~~~~
foo.cc:11:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   11 |         scanf("%lld", &n);
      |         ~~~~~^~~~~~~~~~~~

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