foo.cc: In function 'int main()':
foo.cc:7:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
    7 |  freopen("flip.in","r",stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
foo.cc:8:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
    8 |  freopen("flip.out","w",stdout);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
foo.cc:9:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    9 |  scanf("%d",&t);
      |  ~~~~~^~~~~~~~~
foo.cc:13:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   13 |   scanf("%d",&n);
      |   ~~~~~^~~~~~~~~
foo.cc:16:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   16 |    scanf("%d",&a[i]);
      |    ~~~~~^~~~~~~~~~~~

Found 1 testcases.
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