foo.cc: In function 'int main()':
foo.cc:13:6: error: 'cout' was not declared in this scope
   13 |      cout<<setw(4)<<a*100+b*10+c;
      |      ^~~~
foo.cc:2:1: note: 'std::cout' is defined in header '<iostream>'; did you forget to '#include <iostream>'?
    1 | #include<iomanip>
  +++ |+#include <iostream>
    2 | using namespace std;
foo.cc:16:13: error: 'endl' was not declared in this scope
   16 |       cout<<endl;
      |             ^~~~
foo.cc:2:1: note: 'std::endl' is defined in header '<ostream>'; did you forget to '#include <ostream>'?
    1 | #include<iomanip>
  +++ |+#include <ostream>
    2 | using namespace std;

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