foo.cc: In function 'int main()':
foo.cc:54:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ~~~~~^~~~~~~~~
foo.cc:58:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&a[i]);
   ~~~~~^~~~~~~~~~~~
foo.cc:64:9: warning: 't' may be used uninitialized in this function [-Wmaybe-uninitialized]
   printf("%d",a[i]+2-t);
   ~~~~~~^~~~~~~~~~~~~~~

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