foo.cc: In function 'int main()':
foo.cc:11:6: error: 'i' was not declared in this scope
   11 |  for(i = 0; i<n; i++)
      |      ^
foo.cc:21:6: error: 'i' was not declared in this scope
   21 |  for(i = 0; i<n; i++)
      |      ^
foo.cc:6:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
foo.cc:10:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   10 |   scanf("%d", &a[i]);
      |   ~~~~~^~~~~~~~~~~~~

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