foo.cc:23:8: warning: missing terminating " character
   23 |  cout<<"678 679 689 789;
      |        ^
foo.cc:23:8: error: missing terminating " character
   23 |  cout<<"678 679 689 789;
      |        ^~~~~~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:24:2: error: expected primary-expression before 'return'
   24 |  return 0;
      |  ^~~~~~

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