foo.cc: In function 'int main()':
foo.cc:52:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   52 |  freopen("in.in", "r", stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
foo.cc:57:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   57 |   char s[5]; scanf("%s", s);
      |              ~~~~~^~~~~~~~~

Found 6 testcases.
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