foo.cc: In function 'int main()':
foo.cc:10:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n);
  ~~~~~^~~~~~~~~~
foo.cc:13:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &data[i]);
   ~~~~~^~~~~~~~~~~~~~~~
foo.cc:22:8: warning: ignoring return value of 'int system(const char*)', declared with attribute warn_unused_result [-Wunused-result]
  system("pause");
  ~~~~~~^~~~~~~~~

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