foo.cc: In function 'int main()':
foo.cc:5:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  freopen("score.in","r",stdin);
  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:6:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  freopen("score.out","w",stdout); 
  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

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