foo.cc:17:5: error: 'cout' does not name a type
   17 |     cout<<ans*2;
      |     ^~~~
foo.cc:18:5: error: expected unqualified-id before 'return'
   18 |     return 0;
      |     ^~~~~~
foo.cc:19:1: error: expected declaration before '}' token
   19 | }
      | ^

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