foo.cc: In function 'int main()':
foo.cc:17:18: error: 'a2' was not declared in this scope
      cout<<a[1]<<a2<<a3<<endl;
                  ^~
foo.cc:17:18: note: suggested alternative: 'a'
      cout<<a[1]<<a2<<a3<<endl;
                  ^~
                  a
foo.cc:17:22: error: 'a3' was not declared in this scope
      cout<<a[1]<<a2<<a3<<endl;
                      ^~
foo.cc:17:22: note: suggested alternative: 'a'
      cout<<a[1]<<a2<<a3<<endl;
                      ^~
                      a

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