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:6:4: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    6 |    cin>>a>>b>>c;
      |    ^~~
      |    std::cin
iostream:60:18: note: 'std::cin' declared here
foo.cc:13:5: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   13 |     cout<<a<<" "<<b<<" "<<c;
      |     ^~~~
      |     std::cout
iostream:61:18: note: 'std::cout' declared here
foo.cc:14:17: error: expected ';' before '}' token
   14 |         return 0
      |                 ^
      |                 ;
   15 | }
      | ~                

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