foo.cc: In function 'int main()':
foo.cc:11:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   11 |  freopen ("water.in","r",stdin);
      |  ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:12:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   12 |  freopen ("water.out","w",stdout);
      |  ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:15:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   15 |  scanf ("%d",&n);
      |  ~~~~~~^~~~~~~~~
foo.cc:17:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   17 |  scanf ("%d",&a[i].d);
      |  ~~~~~~^~~~~~~~~~~~~~
foo.cc:27:9: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
   27 |  printf ("%.2lf",ans/n);
      |  ~~~~~~~^~~~~~~~~~~~~~~
foo.cc:22:3: warning: 's' may be used uninitialized in this function [-Wmaybe-uninitialized]
   22 |  s+=a[i].d;
      |  ~^~~~~~~~

Found 10 testcases.
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