foo.cc: In function 'int main()':
foo.cc:5:2: error: 'array' was not declared in this scope
  array<int,4> arr;
  ^~~~~
foo.cc:5:2: note: suggested alternative:
In file included from foo.cc:2:0:
/usr/include/c++/7/array:94:12: note:   'std::array'
     struct array
            ^~~~~
foo.cc:5:8: error: expected primary-expression before 'int'
  array<int,4> arr;
        ^~~

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