foo.cc: In function 'int main()':
foo.cc:13:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   13 | scanf("%d",&N);
      | ~~~~~^~~~~~~~~
foo.cc:20:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   20 |     scanf("%d",&v[i]);
      |     ~~~~~^~~~~~~~~~~~
foo.cc:21:8: warning: 'sum' may be used uninitialized in this function [-Wmaybe-uninitialized]
   21 |     sum+=v[i];
      |     ~~~^~~~~~

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