foo.cc: In function 'int main()':
foo.cc:10:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   10 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
foo.cc:36:11: warning: ignoring return value of 'int system(const char*)', declared with attribute warn_unused_result [-Wunused-result]
   36 |     system("pause");
      |     ~~~~~~^~~~~~~~~

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