foo.cc: In function 'int main()':
foo.cc:26:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   26 |     freopen("prime.in","r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:27:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   27 |     freopen("prime.out","w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:29:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   29 |     scanf("%d", &t);
      |     ~~~~~^~~~~~~~~~
foo.cc:32:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   32 |         scanf("%d", &n);
      |         ~~~~~^~~~~~~~~~

Found 10 testcases.
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