foo.cc: In function 'int main()':
foo.cc:16:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   16 |  freopen("gem.in","r",stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~
foo.cc:17:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   17 |  freopen("gem.out","w",stdout);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

Found 10 testcases.
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