foo.cc: In function 'int main()':
foo.cc:7:2: error: 'cout' was not declared in this scope
  cout<<x+y<<endl;
  ^~~~
foo.cc:7:13: error: 'endl' was not declared in this scope
  cout<<x+y<<endl;
             ^~~~
foo.cc:7:13: note: suggested alternative: 'enum'
  cout<<x+y<<endl;
             ^~~~
             enum

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