foo.cc: In function 'int main()':
foo.cc:5:8: error: 'i' was not declared in this scope
  int a[i];
        ^
foo.cc:6:7: error: 'a' was not declared in this scope
  cin>>a[i];
       ^
foo.cc:7:2: error: 'n' was not declared in this scope
  n=a[0];
  ^

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