foo.cc:3:1: error: expected identifier before 'int'
    3 | int main()
      | ^~~
foo.cc:2:16: error: expected ';' before 'int'
    2 | using namespace
      |                ^
      |                ;
    3 | int main()
      | ~~~             
foo.cc: In function 'int main()':
foo.cc:5:9: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    5 |         cin>>score;
      |         ^~~
      |         std::cin
iostream:60:18: note: 'std::cin' declared here
foo.cc:5:14: error: 'score' was not declared in this scope
    5 |         cin>>score;
      |              ^~~~~
foo.cc:10:25: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   10 |                         cout<<"A";
      |                         ^~~~
      |                         std::cout
iostream:61:18: note: 'std::cout' declared here
foo.cc:21:24: error: expected ':' before numeric constant
   21 |                 default 3:
      |                        ^~
      |                        :
foo.cc:21:26: error: expected ';' before ':' token
   21 |                 default 3:
      |                          ^
      |                          ;
foo.cc:21:25: warning: statement has no effect [-Wunused-value]
   21 |                 default 3:
      |                         ^
foo.cc:23:24: error: expected ';' before '}' token
   23 |         return 0
      |                 ^       
      |                        ;
   24 |         }
      |         ~        

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