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]
     scanf("%d", &t);
     ~~~~~^~~~~~~~~~
foo.cc:14:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &n);
         ~~~~~^~~~~~~~~~
foo.cc:17:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d", &num[i]);
             ~~~~~^~~~~~~~~~~~~~~

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